Ad-Hoc Autoconfiguration Broadcast Chaire Cisco Constrained Networks IETF Jitter LLN LOADng MANET MANET Broadcast MESH MPR Multicast NHDP OLSR OLSR Security OLSRv2 OSPF OSPF4MANET Performance Evaluation RFC RPL Security segment routing Sensor Networks Smart Grid SMF SOGRID Standard
2018 |
Desmouceaux, Yoann; Townsley, Mark; Clausen, Thomas Zero-Loss Virtual Machine Migration with IPv6 Segment Routing Inproceedings Forthcoming Proceedings 1st SR+SFC Workshop at IEEE CNSM, Forthcoming. Abstract | BibTeX | Tags: Chaire Cisco, segment routing @inproceedings{Desmouceaux2018e, title = {Zero-Loss Virtual Machine Migration with IPv6 Segment Routing}, author = {Yoann Desmouceaux and Mark Townsley and Thomas Clausen}, year = {2018}, date = {2018-11-01}, booktitle = {Proceedings 1st SR+SFC Workshop at IEEE CNSM}, abstract = {With the development of large-scale data centers, Virtual Machine (VM) migration is a key component for resource optimization, cost reduction, and maintenance. From a network perspective, traditional VM migration mechanisms rely on the hypervisor running at the destination host advertising the new location of the VM once migration is complete. However, this creates a period of time during which the VM is not reachable, yielding packet loss. This paper introduces a method to perform zero-loss VM migration by using IPv6 Segment Routing (SR). Rather than letting the hypervisor update a locator mapping after VM migration is complete, a logical path consisting of the source and destination hosts is pre-provisioned. Packets destined to the migrating VM are sent through this path using SR, shortly before, during, and shortly after migration – the virtual router on the source host being in charge of forwarding packets locally if the VM migration has not completed yet, or to the destination host otherwise. The proposed mechanism is implemented as a VPP plugin, and feasibility of zero-loss VM migration is demonstrated with various workloads. Evaluation shows that this yields benefits in terms of session opening latency and TCP throughput.}, keywords = {Chaire Cisco, segment routing}, pubstate = {forthcoming}, tppubtype = {inproceedings} } With the development of large-scale data centers, Virtual Machine (VM) migration is a key component for resource optimization, cost reduction, and maintenance. From a network perspective, traditional VM migration mechanisms rely on the hypervisor running at the destination host advertising the new location of the VM once migration is complete. However, this creates a period of time during which the VM is not reachable, yielding packet loss. This paper introduces a method to perform zero-loss VM migration by using IPv6 Segment Routing (SR). Rather than letting the hypervisor update a locator mapping after VM migration is complete, a logical path consisting of the source and destination hosts is pre-provisioned. Packets destined to the migrating VM are sent through this path using SR, shortly before, during, and shortly after migration – the virtual router on the source host being in charge of forwarding packets locally if the VM migration has not completed yet, or to the destination host otherwise. The proposed mechanism is implemented as a VPP plugin, and feasibility of zero-loss VM migration is demonstrated with various workloads. Evaluation shows that this yields benefits in terms of session opening latency and TCP throughput. |
Toussaint, Arthur; Hawari, Mohammed; Clausen, Thomas Chasing Linux Jitter Sources for Uncompressed Video Incollection Forthcoming In Proceedings of the 1st Workshop on High-Precision Networks Operations and Control (HiPNet 2018) ad the IEEE 14th International Conference on Network and Service Management (CNSM), Forthcoming. Abstract | BibTeX | Tags: Chaire Cisco, Linux, Network Greedy Applications, Performance @incollection{Toussaint2018, title = {Chasing Linux Jitter Sources for Uncompressed Video}, author = {Arthur Toussaint and Mohammed Hawari and Thomas Clausen}, year = {2018}, date = {2018-11-01}, booktitle = {In Proceedings of the 1st Workshop on High-Precision Networks Operations and Control (HiPNet 2018) ad the IEEE 14th International Conference on Network and Service Management (CNSM)}, abstract = {Beyond the transport of uncompressed video over IP networks, defined in standards such as ST2022-6, the ability to build software-based Video Processing Functions (VPF) on commodity hardware and using general purpose Operating Systems is the next logical step in the evolution of the media industry towards an “all-IP” world. In that context, understand- ing the jitter induced on an ST2022-6 stream by a commodity platform is essential. This paper describes a general methodology to enumerate jitter sources on commodity platforms and to quantify their relative contribution to the overall system jitter. The methodology is applied to the Linux kernel, producing a classification of the different sources of jitter, and a quantification of their impact.}, keywords = {Chaire Cisco, Linux, Network Greedy Applications, Performance}, pubstate = {forthcoming}, tppubtype = {incollection} } Beyond the transport of uncompressed video over IP networks, defined in standards such as ST2022-6, the ability to build software-based Video Processing Functions (VPF) on commodity hardware and using general purpose Operating Systems is the next logical step in the evolution of the media industry towards an “all-IP” world. In that context, understand- ing the jitter induced on an ST2022-6 stream by a commodity platform is essential. This paper describes a general methodology to enumerate jitter sources on commodity platforms and to quantify their relative contribution to the overall system jitter. The methodology is applied to the Linux kernel, producing a classification of the different sources of jitter, and a quantification of their impact. |
Pit--Claudel, Benoit; Desmouceaux, Yoann; Pfister, Pierre; Townsley, Mark; Clausen, Thomas Stateless Load-Aware Load Balancing in P4 Inproceedings 1st P4 European Workshop (P4EU), 2018. Abstract | Links | BibTeX | Tags: Chaire Cisco, load balancing, NetFPGA, segment routing @inproceedings{Pit--Claudel2018, title = {Stateless Load-Aware Load Balancing in P4}, author = {Benoit Pit--Claudel and Yoann Desmouceaux and Pierre Pfister and Mark Townsley and Thomas Clausen}, url = {http://www.thomasclausen.net/en/p4eu-2018/}, year = {2018}, date = {2018-09-24}, publisher = {1st P4 European Workshop (P4EU)}, abstract = {Leveraging the performance opportunities offered by programmable hardware, stateless load-balancing architectures allowing line-rate processing are appealing. Moreover, it has been demonstrated that significantly fairer load-balancing can be achieved by an architecture that considers the actual load of application instances when dispatching connection requests. Architectures which maintain per-connection state for resiliency and/or track application load state for fairness are, however, at odds with hardware-imposed memory constraints. Thus, a desirable load-balancer for programmable hardware would be both stateless and able to dispatch queries to application instances according to their current load. This paper presents SHELL, a stateless application-aware load-balancer combining (i) a power-of-choices scheme using IPv6 Segment Routing to dispatch new flows to a suitable application instance from among multiple candidates, and (ii) the use of a covert channel to record/report which flow was assigned to which candidate in a stateless fashion. In addition, consistent hashing versioning is used to ensure that connections are maintained to the correct application instance, using Segment Routing to “browse” through the history when needed. The stateless design of SHELL makes it suitable for hardware implementation, and this paper describes the implementation of a P4-NetFPGA prototype. A performance evaluation of this SHELL implementation demonstrates throughput and latency characteristics comparable to other stateless load-balancing implementations, while enabling application instance-load-aware dispatching and significantly increasing per-connection consistency resiliency.}, keywords = {Chaire Cisco, load balancing, NetFPGA, segment routing}, pubstate = {published}, tppubtype = {inproceedings} } Leveraging the performance opportunities offered by programmable hardware, stateless load-balancing architectures allowing line-rate processing are appealing. Moreover, it has been demonstrated that significantly fairer load-balancing can be achieved by an architecture that considers the actual load of application instances when dispatching connection requests. Architectures which maintain per-connection state for resiliency and/or track application load state for fairness are, however, at odds with hardware-imposed memory constraints. Thus, a desirable load-balancer for programmable hardware would be both stateless and able to dispatch queries to application instances according to their current load. This paper presents SHELL, a stateless application-aware load-balancer combining (i) a power-of-choices scheme using IPv6 Segment Routing to dispatch new flows to a suitable application instance from among multiple candidates, and (ii) the use of a covert channel to record/report which flow was assigned to which candidate in a stateless fashion. In addition, consistent hashing versioning is used to ensure that connections are maintained to the correct application instance, using Segment Routing to “browse” through the history when needed. The stateless design of SHELL makes it suitable for hardware implementation, and this paper describes the implementation of a P4-NetFPGA prototype. A performance evaluation of this SHELL implementation demonstrates throughput and latency characteristics comparable to other stateless load-balancing implementations, while enabling application instance-load-aware dispatching and significantly increasing per-connection consistency resiliency. |
Desmouceaux, Yoann; Cordero, Juan Antonio; Clausen, Thomas Reliable B.I.E.R. with Peer Caching Journal Article Forthcoming Forthcoming. Abstract | BibTeX | Tags: B.I.E.R., Chaire Cisco, Internet Broadcast, Performance Evaluation, Reliable Content Distribution @article{Desmouceaux2018c, title = {Reliable B.I.E.R. with Peer Caching}, author = {Yoann Desmouceaux and Juan Antonio Cordero and Thomas Clausen}, year = {2018}, date = {2018-06-01}, abstract = {Multicast protocols usually require building multicast trees and maintaining state in intermediate routers, incurring operation complexity. B.I.E.R. (Bit-Indexed Explicit Replication) ambitions to alleviate this complexity by allowing for source-driven selection of destinations and state-less packet forwarding. B.I.E.R. can also be used to achieve reliable delivery of content, by retransmitting packet to the exact set of destinations which have missed it. While B.I.E.R.- based reliable multicast exhibits attractive performance attributes, repair of a lost packet is achieved through source retransmissions, which may be costly and even unnecessary if close peers are able to provide a copy of the packet. Thus, this paper extends the use of reliable B.I.E.R. multicast to allow recoveries from peers, using Segment Routing (SR) to steer retransmission requests through potential candidates. A framework is introduced, which can accommodate different policies for the selection of candidate peers for retransmissions. Simple (both static and adaptive) policies are introduced and analyzed, both (i) theoretically and (ii) by way of simulations in data-center-like and real-world topologies. Results indicate that local peer recovery is able to substantially reduce the overall retransmission traffic, and that this can be achieved through simple policies, where no signaling is required to build a set of candidate peers.}, keywords = {B.I.E.R., Chaire Cisco, Internet Broadcast, Performance Evaluation, Reliable Content Distribution}, pubstate = {forthcoming}, tppubtype = {article} } Multicast protocols usually require building multicast trees and maintaining state in intermediate routers, incurring operation complexity. B.I.E.R. (Bit-Indexed Explicit Replication) ambitions to alleviate this complexity by allowing for source-driven selection of destinations and state-less packet forwarding. B.I.E.R. can also be used to achieve reliable delivery of content, by retransmitting packet to the exact set of destinations which have missed it. While B.I.E.R.- based reliable multicast exhibits attractive performance attributes, repair of a lost packet is achieved through source retransmissions, which may be costly and even unnecessary if close peers are able to provide a copy of the packet. Thus, this paper extends the use of reliable B.I.E.R. multicast to allow recoveries from peers, using Segment Routing (SR) to steer retransmission requests through potential candidates. A framework is introduced, which can accommodate different policies for the selection of candidate peers for retransmissions. Simple (both static and adaptive) policies are introduced and analyzed, both (i) theoretically and (ii) by way of simulations in data-center-like and real-world topologies. Results indicate that local peer recovery is able to substantially reduce the overall retransmission traffic, and that this can be achieved through simple policies, where no signaling is required to build a set of candidate peers. |
Cordero, Juan Antonio; Lou, Wei Take your time, get it closer: content dissemination within mobile pedestrian crowds Journal Article Wireless Networks, 2018, ISSN: 1572-8196. Abstract | Links | BibTeX | Tags: Ad-Hoc, Chaire Cisco, MESH @article{Cordero2018, title = {Take your time, get it closer: content dissemination within mobile pedestrian crowds}, author = {Juan Antonio Cordero and Wei Lou}, url = {https://doi.org/10.1007/s11276-018-1731-2}, doi = {10.1007/s11276-018-1731-2}, issn = {1572-8196}, year = {2018}, date = {2018-05-05}, journal = {Wireless Networks}, abstract = {The explosion of traffic demands in the edge of the Internet, mostly by mobile users, is putting under pressure current networking infrastructures. This is particularly acute when huge amounts of users and active wireless devices gather in reduced geographical spaces, increasing the risk of exceeding planned capacity of deployed infrastructure. This trend motivates research on edge computing, and in particular, on mechanisms to offload or address locally part of the user injected traffic at the access infrastructure, thus reducing the need of Internet requests and retrievals. This paper concentrates on the ability of mobile crowds --and corresponding access networks---to fulfill content requests originated within the mesh, with minimal intervention of the Internet infrastructure. Simple heuristics are revisited, proposed, discussed and evaluated to improve autonomous content discovery and dissemination within high-density, low-mobility crowds, by combining notions already explored for MANET routing: deliberate jittering and autonomous distance-based overlay pruning. Results over synthetic networks and real mobility traces indicate that these mechanisms improve efficiency and quality of content request discoveries, by reducing significantly collisions and increasing stability of discovered paths in dense pedestrian crowds.}, keywords = {Ad-Hoc, Chaire Cisco, MESH}, pubstate = {published}, tppubtype = {article} } The explosion of traffic demands in the edge of the Internet, mostly by mobile users, is putting under pressure current networking infrastructures. This is particularly acute when huge amounts of users and active wireless devices gather in reduced geographical spaces, increasing the risk of exceeding planned capacity of deployed infrastructure. This trend motivates research on edge computing, and in particular, on mechanisms to offload or address locally part of the user injected traffic at the access infrastructure, thus reducing the need of Internet requests and retrievals. This paper concentrates on the ability of mobile crowds --and corresponding access networks---to fulfill content requests originated within the mesh, with minimal intervention of the Internet infrastructure. Simple heuristics are revisited, proposed, discussed and evaluated to improve autonomous content discovery and dissemination within high-density, low-mobility crowds, by combining notions already explored for MANET routing: deliberate jittering and autonomous distance-based overlay pruning. Results over synthetic networks and real mobility traces indicate that these mechanisms improve efficiency and quality of content request discoveries, by reducing significantly collisions and increasing stability of discovered paths in dense pedestrian crowds. |
Clausen, Thomas; YI, Jiazi; Cordero, Juan Antonio; Igarashi, Yuichi Use 'em or Lose 'em: On Unidirectional Links in Reactive Routing Protocols Journal Article Elsevier Ad Hoc Networks, 73 , pp. 51-64, 2018. Abstract | Links | BibTeX | Tags: Ad-Hoc, LLN, LOADng, MANET, Reactive, Routing @article{Clausen2018unidirectional, title = {Use 'em or Lose 'em: On Unidirectional Links in Reactive Routing Protocols}, author = {Thomas Clausen and Jiazi YI and Juan Antonio Cordero and Yuichi Igarashi}, url = {https://ac.els-cdn.com/S1570870518300325/1-s2.0-S1570870518300325-main.pdf?_tid=0b7f4a7e-b489-4317-b96c-f18cec2af56f&acdnat=1520779362_84dbf04f92cfc3c7ef2448f3b4c3ebf7}, doi = {10.1016/j.adhoc.2018.02.004}, year = {2018}, date = {2018-05-01}, journal = {Elsevier Ad Hoc Networks}, volume = {73}, pages = {51-64}, abstract = {In reactive unicast routing protocols, Route Discovery aims to include only bidirectional links in discovered routing paths. This is typically accomplished by having routers maintain a “blacklist” of links recently confirmed (through Route Reply processing) to be unidirectional – which is then used for excluding subsequent Route Discovery control messages received over these links from being processed and forwarded. This paper first presents an analytical model, which allows to study the impact of unidirectional links being present in a network, on the performance of reactive routing protocols. Next, this paper identifies that despite the use of a “blacklist”, the Route Discovery process may result in discovery of false forward routes, i.e., routes containing unidirec- tional links – and proposes a counter-measure denoted Forward Bidirectionality Check. This paper further proposes a Loop Exploration mechanism, allowing to properly include unidirectional links in a discovered routing topology – with the goal of providing bidirectional connectivity even in absence of bidirectional paths in the network. Finally, each of these proposed mechanisms are subjected to extensive network simulations in static scenarios. When the fraction of unidirectional links is moderate (15 50%), simulations find Forward Bidirectionality Check to significantly increase the probability that bidirectional routing paths can be discovered by a reactive routing protocol, while incurring only an insignificant additional overhead. Further, in networks with a significant fraction of unidirectional links ( 50%), simulations reveal that Loop Exploration preserves the ability of a reactive routing protocol to establish bidirectional communication (possibly through non-bidirectional paths), but at the expense of a substantial additional overhead.}, keywords = {Ad-Hoc, LLN, LOADng, MANET, Reactive, Routing}, pubstate = {published}, tppubtype = {article} } In reactive unicast routing protocols, Route Discovery aims to include only bidirectional links in discovered routing paths. This is typically accomplished by having routers maintain a “blacklist” of links recently confirmed (through Route Reply processing) to be unidirectional – which is then used for excluding subsequent Route Discovery control messages received over these links from being processed and forwarded. This paper first presents an analytical model, which allows to study the impact of unidirectional links being present in a network, on the performance of reactive routing protocols. Next, this paper identifies that despite the use of a “blacklist”, the Route Discovery process may result in discovery of false forward routes, i.e., routes containing unidirec- tional links – and proposes a counter-measure denoted Forward Bidirectionality Check. This paper further proposes a Loop Exploration mechanism, allowing to properly include unidirectional links in a discovered routing topology – with the goal of providing bidirectional connectivity even in absence of bidirectional paths in the network. Finally, each of these proposed mechanisms are subjected to extensive network simulations in static scenarios. When the fraction of unidirectional links is moderate (15 50%), simulations find Forward Bidirectionality Check to significantly increase the probability that bidirectional routing paths can be discovered by a reactive routing protocol, while incurring only an insignificant additional overhead. Further, in networks with a significant fraction of unidirectional links ( 50%), simulations reveal that Loop Exploration preserves the ability of a reactive routing protocol to establish bidirectional communication (possibly through non-bidirectional paths), but at the expense of a substantial additional overhead. |
Desmouceaux, Yoann; Toubaline, Sonia; Clausen, Thomas Flow-Aware Workload Migration in Data Centers Journal Article Springer - Journal of Network and Systems Management (JONS), 2018. Abstract | Links | BibTeX | Tags: Chaire Cisco, dc-optimization, Infrastructure for Big Data @article{Desmouceaux2018a, title = {Flow-Aware Workload Migration in Data Centers}, author = {Yoann Desmouceaux and Sonia Toubaline and Thomas Clausen}, url = {https://link.springer.com/epdf/10.1007/s10922-018-9452-5?author_access_token=qm_40d91CsNLlZ_vZ0tZFPe4RwlQNchNByi7wbcMAY4xSrvbLplDMLQ3AN9vWEoUIxtZAIdnOGAzJH5W3YOrbGteOLvaEXsEE1xFv66lVxTKlL40BAS25fsaLf8w1RJAvY69owHWqhJkTmAZpvdCkQ%3D%3D https://www.epizeuxis.net/wp-content/uploads/2018/03/jons-2018.pdf}, doi = {10.1007/s10922-018-9452-5}, year = {2018}, date = {2018-03-10}, journal = {Springer - Journal of Network and Systems Management (JONS)}, abstract = {In data centers, subject to workloads with heterogeneous (and sometimes short) lifetimes, workload migration is a way of attaining a more efficient utilization of the underlying physical machines. To not introduce performance degradation, such workload migration must take into account not only machine resources, and per-task resource requirements, but also application dependencies in terms of network communication. This articleformat presents a workload migration model capturing all of these constraints. A linear programming framework is developed allowing accurate representation of per-task resources requirements and inter-task network demands. Using this, a multi-objective problem is formulated to compute a re-allocation of tasks that (i) maximizes the total inter-task throughput, while (ii) minimizing the cost incurred by migration and (iii) allocating the maximum number of new tasks. A baseline algorithm, solving this multi-objective problem using the $epsilon$-constraint method is proposed, in order to generate the set of Pareto-optimal solutions. As this algorithm is compute-intensive for large topologies, a heuristic, which computes an approximation of the Pareto front, is then developed, and evaluated on different topologies and with different machine load factors. These evaluations show that the heuristic can provide close-to-optimal solutions, while reducing the solving time by one to two order of magnitudes. }, keywords = {Chaire Cisco, dc-optimization, Infrastructure for Big Data}, pubstate = {published}, tppubtype = {article} } In data centers, subject to workloads with heterogeneous (and sometimes short) lifetimes, workload migration is a way of attaining a more efficient utilization of the underlying physical machines. To not introduce performance degradation, such workload migration must take into account not only machine resources, and per-task resource requirements, but also application dependencies in terms of network communication. This articleformat presents a workload migration model capturing all of these constraints. A linear programming framework is developed allowing accurate representation of per-task resources requirements and inter-task network demands. Using this, a multi-objective problem is formulated to compute a re-allocation of tasks that (i) maximizes the total inter-task throughput, while (ii) minimizing the cost incurred by migration and (iii) allocating the maximum number of new tasks. A baseline algorithm, solving this multi-objective problem using the $epsilon$-constraint method is proposed, in order to generate the set of Pareto-optimal solutions. As this algorithm is compute-intensive for large topologies, a heuristic, which computes an approximation of the Pareto front, is then developed, and evaluated on different topologies and with different machine load factors. These evaluations show that the heuristic can provide close-to-optimal solutions, while reducing the solving time by one to two order of magnitudes. |
Desmouceaux, Yoann; Clausen, Thomas; Cordero, Juan Antonio; Townsley, Mark W Reliable Multicast with B.I.E.R. Journal Article Forthcoming IEEE/KICS Journal of Communications and Networks (JCN), 20 (2), pp. 182-197, Forthcoming. Abstract | Links | BibTeX | Tags: B.I.E.R., Broadcast, Chaire Cisco, Internet Broadcast, Multicast, Performance Evaluation, Reliable Content Distribution @article{Desmouceaux0000, title = {Reliable Multicast with B.I.E.R.}, author = {Yoann Desmouceaux and Thomas Clausen and Juan Antonio Cordero and W. Mark Townsley }, url = {http://www.thomasclausen.net/wp-content/uploads/2018/03/jcn-2018.pdf}, year = {2018}, date = {2018-02-28}, journal = {IEEE/KICS Journal of Communications and Networks (JCN)}, volume = {20}, number = {2}, pages = {182-197}, abstract = {Inter-network multicast protocols, which build and maintain multicast trees, incur both explicit protocol signalling, and maintenance of state in intermediate routers in the network. B.I.E.R. (Bit-Indexed Explicit Replication) is a technique which can provide a multicast service yet removes such complexities: in- termediate routers are unencumbered by group management, and no per-group state is to be maintained. This paper explores the use of B.I.E.R. as a basis for develop- ing an efficient and reliable multicast mechanism, where redun- dant traffic is avoided, essential traffic is forwarded along shortest paths, and no per-flow state is required in intermediate routers. Evaluated by way of both an analytical model and network sim- ulation both in generic and in real network topologies with vary- ing background traffic loads, the proposed B.I.E.R.-based reliable multicast mechanism exhibits attractive performance attributes: it attains delivery success rates as high as any other reliable multicast service, but with significantly better link utilisation and no per-flow or per-group state in intermediate routers of the network.}, keywords = {B.I.E.R., Broadcast, Chaire Cisco, Internet Broadcast, Multicast, Performance Evaluation, Reliable Content Distribution}, pubstate = {forthcoming}, tppubtype = {article} } Inter-network multicast protocols, which build and maintain multicast trees, incur both explicit protocol signalling, and maintenance of state in intermediate routers in the network. B.I.E.R. (Bit-Indexed Explicit Replication) is a technique which can provide a multicast service yet removes such complexities: in- termediate routers are unencumbered by group management, and no per-group state is to be maintained. This paper explores the use of B.I.E.R. as a basis for develop- ing an efficient and reliable multicast mechanism, where redun- dant traffic is avoided, essential traffic is forwarded along shortest paths, and no per-flow state is required in intermediate routers. Evaluated by way of both an analytical model and network sim- ulation both in generic and in real network topologies with vary- ing background traffic loads, the proposed B.I.E.R.-based reliable multicast mechanism exhibits attractive performance attributes: it attains delivery success rates as high as any other reliable multicast service, but with significantly better link utilisation and no per-flow or per-group state in intermediate routers of the network. |
Desmouceaux, Yoann; Pfister, Pierre; Tollet, Jérôme; Townsley, Mark W; Clausen, Thomas 6LB: Scalable and Application-Aware Load Balancing with Segment Routing Journal Article IEEE/ACM Transactions on Networking, 26 (2), pp. 819-834, 2018, ISSN: 1063-6692. Abstract | Links | BibTeX | Tags: Chaire Cisco, Infrastructure for Big Data, load balancing, Scalability, segment routing @article{Desmouceaux2018, title = {6LB: Scalable and Application-Aware Load Balancing with Segment Routing}, author = {Yoann Desmouceaux and Pierre Pfister and Jérôme Tollet and W. Mark Townsley and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2018/02/2018-IEEE-Transactions-on-Networking-6LB-Scalable-and-Application-Aware-Load-Balancing-with-Segment-Routing.pdf}, doi = {10.1109/TNET.2018.2799242}, issn = {1063-6692}, year = {2018}, date = {2018-02-15}, journal = {IEEE/ACM Transactions on Networking}, volume = {26}, number = {2}, pages = {819-834}, abstract = {Network load-balancers generally either do not take application state into account, or do so at the cost of a central- ized monitoring system. This paper introduces a load-balancer running exclusively within the IP forwarding plane, i.e. in an application protocol agnostic fashion – yet which still provides application-awareness and makes real-time, decentralized deci- sions. To that end, IPv6 Segment Routing is used to direct data packets from a new flow through a chain of candidate servers, until one decides to accept the connection, based solely on its local state. This way, applications themselves naturally decide on how to fairly share incoming connections, while incurring minimal network overhead, and no out-of-band signaling. A consistent hashing algorithm, as well as an in-band stickiness protocol, allow for the proposed solution to be able to be reliably distributed across a large number of instances. Performance evaluation by means of an analytical model and actual tests on different workloads (including a Wikipedia replay as a realistic workload) show significant performance benefits in terms of shorter response times, when compared to a traditional random load-balancer. In addition, this paper introduces and compares kernel bypass high-performance implementations of both 6LB and a state-of-the-art load-balancer, showing that the significant system-level benefits of 6LB are achievable with a negligible data-path CPU overhead.}, keywords = {Chaire Cisco, Infrastructure for Big Data, load balancing, Scalability, segment routing}, pubstate = {published}, tppubtype = {article} } Network load-balancers generally either do not take application state into account, or do so at the cost of a central- ized monitoring system. This paper introduces a load-balancer running exclusively within the IP forwarding plane, i.e. in an application protocol agnostic fashion – yet which still provides application-awareness and makes real-time, decentralized deci- sions. To that end, IPv6 Segment Routing is used to direct data packets from a new flow through a chain of candidate servers, until one decides to accept the connection, based solely on its local state. This way, applications themselves naturally decide on how to fairly share incoming connections, while incurring minimal network overhead, and no out-of-band signaling. A consistent hashing algorithm, as well as an in-band stickiness protocol, allow for the proposed solution to be able to be reliably distributed across a large number of instances. Performance evaluation by means of an analytical model and actual tests on different workloads (including a Wikipedia replay as a realistic workload) show significant performance benefits in terms of shorter response times, when compared to a traditional random load-balancer. In addition, this paper introduces and compares kernel bypass high-performance implementations of both 6LB and a state-of-the-art load-balancer, showing that the significant system-level benefits of 6LB are achievable with a negligible data-path CPU overhead. |
Radu, Dan; Cretu, Adrian; Parrein, Benoit; Yi, Jiazi; Avram, Camelia; Astilean, Adina Flying Ad Hoc Network for Emergency Applications Connected to a Fog System Inproceedings Barolli, Leonard; Xhafa, Fatos; Javaid, Nadeem; Spaho, Evjola; Kolici, Vladi (Ed.): pp. 675–686, Springer International Publishing, Cham, 2018, ISBN: 978-3-319-75928-9. Abstract | Links | BibTeX | Tags: Ad-Hoc, MP-OLSR, Multipath, OLSR @inproceedings{10.1007/978-3-319-75928-9_60, title = {Flying Ad Hoc Network for Emergency Applications Connected to a Fog System}, author = {Dan Radu and Adrian Cretu and Benoit Parrein and Jiazi Yi and Camelia Avram and Adina Astilean}, editor = {Leonard Barolli and Fatos Xhafa and Nadeem Javaid and Evjola Spaho and Vladi Kolici}, url = {https://www.researchgate.net/publication/323361307_Flying_Ad_Hoc_Network_for_Emergency_Applications_Connected_to_a_Fog_System}, doi = {10.1007/978-3-319-75928-9_60}, isbn = {978-3-319-75928-9}, year = {2018}, date = {2018-01-01}, pages = {675--686}, publisher = {Springer International Publishing}, address = {Cham}, abstract = {The main objective of this paper is to improve the efficiency of vegetation fire emergency interventions by using MP-OLSR routing protocol for data transmission in Flying Ad Hoc NETwork (FANET) applications. The presented conceptual system design could potentially increase the rescuing chances of people caught up in natural disaster environments, the final goal being to provide public safety services to interested parties. The proposed system architecture model relies on emerging technologies (Internet of Things & Fog, Smart Cities, Mobile Ad Hoc Networks) and actual concepts available in the scientific literature. The two main components of the system consist in a FANET, capable of collecting fire detection data from GPS and video enabled drones, and a Fog/Edge node that allows data collection and analysis, but also provides public safety services for interested parties. The sensing nodes forward data packets through multiple mobile hops until they reach the central management system. A proof of concept based on MP-OLSR routing protocol for efficient data transmission in FANET scenarios and possible public safety rescuing services is given.}, keywords = {Ad-Hoc, MP-OLSR, Multipath, OLSR}, pubstate = {published}, tppubtype = {inproceedings} } The main objective of this paper is to improve the efficiency of vegetation fire emergency interventions by using MP-OLSR routing protocol for data transmission in Flying Ad Hoc NETwork (FANET) applications. The presented conceptual system design could potentially increase the rescuing chances of people caught up in natural disaster environments, the final goal being to provide public safety services to interested parties. The proposed system architecture model relies on emerging technologies (Internet of Things & Fog, Smart Cities, Mobile Ad Hoc Networks) and actual concepts available in the scientific literature. The two main components of the system consist in a FANET, capable of collecting fire detection data from GPS and video enabled drones, and a Fog/Edge node that allows data collection and analysis, but also provides public safety services for interested parties. The sensing nodes forward data packets through multiple mobile hops until they reach the central management system. A proof of concept based on MP-OLSR routing protocol for efficient data transmission in FANET scenarios and possible public safety rescuing services is given. |
2017 |
Clausen, Thomas; Yi, Jiazi; Herberg, Ulrich Lightweight On-demand Ad hoc Distance-vector Routing-Next Generation (LOADng): Protocol, Extension, and Applicability Journal Article Computer Networks, 126 , pp. 125-140, 2017. Abstract | Links | BibTeX | Tags: Ad-Hoc, LLN, LOADng @article{clausen2017lightweight, title = {Lightweight On-demand Ad hoc Distance-vector Routing-Next Generation (LOADng): Protocol, Extension, and Applicability}, author = {Thomas Clausen and Jiazi Yi and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2017/08/2017-Computer-Networks-Lightweight-On-demand-Ad-hoc-Distance-vector-Routing-Next-Generation-LOADng.pdf}, doi = {10.1016/j.comnet.2017.06.025}, year = {2017}, date = {2017-10-24}, journal = {Computer Networks}, volume = {126}, pages = {125-140}, publisher = {Elsevier}, abstract = {This paper studies the routing protocol “Lightweight On-demand Ad hoc Distance-vector Routing Protocol – Next Generation (LOADng)”, designed to enable efficient, scalable and secure routing in low power and lossy networks. As a reactive protocol, it does not maintain a routing table for all destinations in the network, but initiates a route discovery to a destination only when there is data to be sent to that destination to reduce routing overhead and memory consumption. Designed with a modular approach, LOADng can be extended with additional components for adapting the protocol to different topologies, traffic, and data-link layer characteristics. This paper studies several such additional components for extending LOADng: support for smart route requests and expanding ring search, an extension permitting maintaining collection trees, a fast rerouting extension. All those extensions are examined from the aspects of specification, interoperability with other mechanisms, security vulnerabilities, performance and applicability. A general framework is also proposed to secure the routing protocol.}, keywords = {Ad-Hoc, LLN, LOADng}, pubstate = {published}, tppubtype = {article} } This paper studies the routing protocol “Lightweight On-demand Ad hoc Distance-vector Routing Protocol – Next Generation (LOADng)”, designed to enable efficient, scalable and secure routing in low power and lossy networks. As a reactive protocol, it does not maintain a routing table for all destinations in the network, but initiates a route discovery to a destination only when there is data to be sent to that destination to reduce routing overhead and memory consumption. Designed with a modular approach, LOADng can be extended with additional components for adapting the protocol to different topologies, traffic, and data-link layer characteristics. This paper studies several such additional components for extending LOADng: support for smart route requests and expanding ring search, an extension permitting maintaining collection trees, a fast rerouting extension. All those extensions are examined from the aspects of specification, interoperability with other mechanisms, security vulnerabilities, performance and applicability. A general framework is also proposed to secure the routing protocol. |
Perez, Samuel; Cordero, Juan Antonio; Coupechoux, Marceau ODMAC++: An IoT Communication Manager based on Energy Harvesting Prediction Inproceedings Proceedings of the IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'2017)., IEEE, 2017. Abstract | BibTeX | Tags: Chaire Cisco, Constrained Networks, IoT, Sensor Networks @inproceedings{Perez2017, title = {ODMAC++: An IoT Communication Manager based on Energy Harvesting Prediction}, author = {Samuel Perez and Juan Antonio Cordero and Marceau Coupechoux}, year = {2017}, date = {2017-10-08}, booktitle = {Proceedings of the IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'2017).}, publisher = {IEEE}, abstract = {In large low-power networks of battery-driven sen- sors, power outages are a major concern and communication rates have to be carefully designed in order to optimize energy consumption, network connectivity and sensors lifetime. In some IoT use cases, power can be supplied to sensors by way of renewable energy automatic harvesting (solar panels, etc.). Given the high variability of energy arrival processes, energy consumption in sensors, in particular caused by transmissions to the sink, has to be aligned with energy harvesting patterns, so as to maximize throughput while avoiding power outages that may arise when the battery is empty. This paper proposes ODMAC++, an extension to a well-known protocol for sensor transmission scheduling in a WSN. ODMAC++ relies on learning techniques to adapt sensors communication rate to energy harvesting patterns, and uses a beaconing mechanism whose frequency is adjusted based on past measurements on the harvested energy process. Simulations based on analytical energy arrival models and on real solar radiation measurements indicate that ODMAC++ is able to avoid power outages and to cope with battery limitation and energy variations due to variability in time.}, keywords = {Chaire Cisco, Constrained Networks, IoT, Sensor Networks}, pubstate = {published}, tppubtype = {inproceedings} } In large low-power networks of battery-driven sen- sors, power outages are a major concern and communication rates have to be carefully designed in order to optimize energy consumption, network connectivity and sensors lifetime. In some IoT use cases, power can be supplied to sensors by way of renewable energy automatic harvesting (solar panels, etc.). Given the high variability of energy arrival processes, energy consumption in sensors, in particular caused by transmissions to the sink, has to be aligned with energy harvesting patterns, so as to maximize throughput while avoiding power outages that may arise when the battery is empty. This paper proposes ODMAC++, an extension to a well-known protocol for sensor transmission scheduling in a WSN. ODMAC++ relies on learning techniques to adapt sensors communication rate to energy harvesting patterns, and uses a beaconing mechanism whose frequency is adjusted based on past measurements on the harvested energy process. Simulations based on analytical energy arrival models and on real solar radiation measurements indicate that ODMAC++ is able to avoid power outages and to cope with battery limitation and energy variations due to variability in time. |
Desmouceaux, Yoann; Pfister, Pierre; Tollet, Jerome; Townsley, Mark W; Clausen, Thomas SRLB: The Power of Choices in Load Balancing with Segment Routing Inproceedings In Proceedings of the 37th IEEE International Conference on Distributed Computing Systems (ICDCS), 2017. Abstract | Links | BibTeX | Tags: Chaire Cisco, dc-optimization, Infrastructure for Big Data, load balancing, segment routing @inproceedings{Desmouceaux2017b, title = {SRLB: The Power of Choices in Load Balancing with Segment Routing}, author = {Yoann Desmouceaux and Pierre Pfister and Jerome Tollet and W. Mark Townsley and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2017/05/camera-ready-ieeepdfexpress.pdf}, year = {2017}, date = {2017-06-05}, booktitle = {In Proceedings of the 37th IEEE International Conference on Distributed Computing Systems (ICDCS)}, abstract = {Network load-balancers generally either do not take application state into account, or do so at the cost of a central- ized monitoring system. This paper introduces a load-balancer running exclusively within the IP forwarding plane, i.e. in an application protocol agnostic fashion – yet which still provides application-awareness and makes real-time, decentralized deci- sions. To that end, IPv6 Segment Routing is used to direct data packets from a new flow through a chain of candidate servers, until one decides to accept the connection, based on its local state. This way, applications themselves naturally decide on how to share incoming connections, while incurring minimal network overhead, and no out-of-band signaling. Tests on different workloads – including realistic workloads such as replaying actual Wikipedia access traffic towards a set of replica Wikipedia instances – show significant performance benefits, in terms of shorter response times, when compared to a traditional random load-balancer.}, keywords = {Chaire Cisco, dc-optimization, Infrastructure for Big Data, load balancing, segment routing}, pubstate = {published}, tppubtype = {inproceedings} } Network load-balancers generally either do not take application state into account, or do so at the cost of a central- ized monitoring system. This paper introduces a load-balancer running exclusively within the IP forwarding plane, i.e. in an application protocol agnostic fashion – yet which still provides application-awareness and makes real-time, decentralized deci- sions. To that end, IPv6 Segment Routing is used to direct data packets from a new flow through a chain of candidate servers, until one decides to accept the connection, based on its local state. This way, applications themselves naturally decide on how to share incoming connections, while incurring minimal network overhead, and no out-of-band signaling. Tests on different workloads – including realistic workloads such as replaying actual Wikipedia access traffic towards a set of replica Wikipedia instances – show significant performance benefits, in terms of shorter response times, when compared to a traditional random load-balancer. |
Clausen, Thomas; Herberg, Ulrich; Yi, Jiazi RFC8116: Security Threats to the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous RFC 8116, 2017. Abstract | Links | BibTeX | Tags: Ad-Hoc, MANET, MESH, OLSR Security, OLSRv2, RFC, Security @misc{rfc8116, title = {RFC8116: Security Threats to the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Thomas Clausen and Ulrich Herberg and Jiazi Yi}, url = {http://www.thomasclausen.net/wp-content/uploads/2017/05/rfc8116.pdf}, doi = {10.17487/rfc8116}, year = {2017}, date = {2017-01-01}, number = {8116}, publisher = {RFC Editor}, series = {Request for Comments}, abstract = {This document analyzes common security threats to the Optimized Link State Routing Protocol version 2 (OLSRv2) and describes their potential impacts on Mobile Ad Hoc Network (MANET) operations. It also analyzes which of these security vulnerabilities can be mitigated when using the mandatory-to-implement security mechanisms for OLSRv2 and how the vulnerabilities are mitigated.}, howpublished = {RFC 8116}, keywords = {Ad-Hoc, MANET, MESH, OLSR Security, OLSRv2, RFC, Security}, pubstate = {published}, tppubtype = {misc} } This document analyzes common security threats to the Optimized Link State Routing Protocol version 2 (OLSRv2) and describes their potential impacts on Mobile Ad Hoc Network (MANET) operations. It also analyzes which of these security vulnerabilities can be mitigated when using the mandatory-to-implement security mechanisms for OLSRv2 and how the vulnerabilities are mitigated. |
Yi, Jiazi; Parrein, Benoit RFC8218: Multipath Extension for the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous RFC 8218, 2017. Abstract | Links | BibTeX | Tags: Ad-Hoc, MANET, MP-OLSR, OLSRv2, RFC @misc{rfc8218, title = {RFC8218: Multipath Extension for the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Jiazi Yi and Benoit Parrein}, url = {https://rfc-editor.org/rfc/rfc8218.txt}, doi = {10.17487/RFC8218}, year = {2017}, date = {2017-01-01}, number = {8218}, publisher = {RFC Editor}, series = {Request for Comments}, abstract = {This document specifies a multipath extension for the Optimized Link State Routing Protocol version 2 (OLSRv2) to discover multiple disjoint paths for Mobile Ad Hoc Networks (MANETs). Considering the characteristics of MANETs, especially the dynamic network topology, using multiple paths can increase aggregated throughput and improve the reliability by avoiding single route failures. The interoperability with OLSRv2 is retained.}, howpublished = {RFC 8218}, keywords = {Ad-Hoc, MANET, MP-OLSR, OLSRv2, RFC}, pubstate = {published}, tppubtype = {misc} } This document specifies a multipath extension for the Optimized Link State Routing Protocol version 2 (OLSRv2) to discover multiple disjoint paths for Mobile Ad Hoc Networks (MANETs). Considering the characteristics of MANETs, especially the dynamic network topology, using multiple paths can increase aggregated throughput and improve the reliability by avoiding single route failures. The interoperability with OLSRv2 is retained. |
Clausen, Thomas H; Herberg, Ulrich; Yi, Jiazi Security Threats to the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous RFC 8116, 2017. Abstract | Links | BibTeX | Tags: @misc{RFC8116b, title = {Security Threats to the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Thomas H Clausen and Ulrich Herberg and Jiazi Yi}, url = {https://rfc-editor.org/rfc/rfc8116.txt}, doi = {10.17487/RFC8116}, year = {2017}, date = {2017-01-01}, number = {8116}, publisher = {RFC Editor}, series = {Request for Comments}, abstract = {This document analyzes common security threats to the Optimized Link State Routing Protocol version 2 (OLSRv2) and describes their potential impacts on Mobile Ad Hoc Network (MANET) operations. It also analyzes which of these security vulnerabilities can be mitigated when using the mandatory-to-implement security mechanisms for OLSRv2 and how the vulnerabilities are mitigated.}, howpublished = {RFC 8116}, keywords = {}, pubstate = {published}, tppubtype = {misc} } This document analyzes common security threats to the Optimized Link State Routing Protocol version 2 (OLSRv2) and describes their potential impacts on Mobile Ad Hoc Network (MANET) operations. It also analyzes which of these security vulnerabilities can be mitigated when using the mandatory-to-implement security mechanisms for OLSRv2 and how the vulnerabilities are mitigated. |
2016 |
Clausen, Thomas; Yi, Jiazi; Herberg, Ulrich RFC7985: Security Threats to Simplified Multicast Forwarding (SMF) Miscellaneous IETF - Informational RFC 7985, 2016, ISSN: 2070-1721. Abstract | Links | BibTeX | Tags: MANET, MESH, RFC, Security, SMF, SMF Security @misc{RFC7985, title = {RFC7985: Security Threats to Simplified Multicast Forwarding (SMF)}, author = {Thomas Clausen and Jiazi Yi and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2016/11/rfc7985.txt.pdf}, doi = {http://dx.doi.org/10.17487/RFC7985}, issn = {2070-1721}, year = {2016}, date = {2016-11-02}, abstract = {This document analyzes security threats to Simplified Multicast Forwarding (SMF), including vulnerabilities of duplicate packet detection and relay set selection mechanisms. This document is not intended to propose solutions to the threats described. In addition, this document updates RFC 7186 regarding threats to the relay set selection mechanisms using the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) (RFC 6130)}, howpublished = {IETF - Informational RFC 7985}, keywords = {MANET, MESH, RFC, Security, SMF, SMF Security}, pubstate = {published}, tppubtype = {misc} } This document analyzes security threats to Simplified Multicast Forwarding (SMF), including vulnerabilities of duplicate packet detection and relay set selection mechanisms. This document is not intended to propose solutions to the threats described. In addition, this document updates RFC 7186 regarding threats to the relay set selection mechanisms using the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) (RFC 6130) |
Augustin, Aloys; Yi, Jiazi; Clausen, Thomas; Townsley, Mark A Study of LoRa: Long Range & Low Power Networks for the Internet of Things Journal Article MDPI Sensors, 16 (9), pp. 1466, 2016, ISSN: 1424-8220, ((5 yr Impact Factor: 2.437)). Abstract | Links | BibTeX | Tags: Chaire Cisco, IoT, LLN, LoRA, LPWAN, Sensor Networks @article{Augustin2016, title = {A Study of LoRa: Long Range & Low Power Networks for the Internet of Things}, author = {Aloys Augustin and Jiazi Yi and Thomas Clausen and Mark Townsley}, url = {http://www.thomasclausen.net/2016-a-study-of-lora-long-range-low-power-networks-for-the-internet-of-things/}, doi = {10.3390/s16091466}, issn = {1424-8220}, year = {2016}, date = {2016-09-09}, journal = {MDPI Sensors}, volume = {16}, number = {9}, pages = {1466}, abstract = {LoRa is a long-range, low-power, low-bitrate, wireless telecommunications system, promoted as an infrastructure solution for the Internet of Things: end-devices use LoRa across a single wireless hop to communicate to gateway(s), connected to the Internet and which act as transparent bridges and relay messages between these end-devices and a central network server. This paper provides an overview of LoRa and an in-depth analysis of its functional components. The physical and data link layer performance is evaluated by field tests and simulations. Based on the analysis and evaluations, some possible solutions for performance enhancements are proposed.}, note = {(5 yr Impact Factor: 2.437)}, keywords = {Chaire Cisco, IoT, LLN, LoRA, LPWAN, Sensor Networks}, pubstate = {published}, tppubtype = {article} } LoRa is a long-range, low-power, low-bitrate, wireless telecommunications system, promoted as an infrastructure solution for the Internet of Things: end-devices use LoRa across a single wireless hop to communicate to gateway(s), connected to the Internet and which act as transparent bridges and relay messages between these end-devices and a central network server. This paper provides an overview of LoRa and an in-depth analysis of its functional components. The physical and data link layer performance is evaluated by field tests and simulations. Based on the analysis and evaluations, some possible solutions for performance enhancements are proposed. |
Cordero, Juan Antonio; Lou, Wei Not So Far: Improving Autonomous Content Discovery and Delivery within Mobile Pedestrian Crowds Inproceedings Proceedings of the 25th International Conference on Computer Communication and Networks (ICCCN 2016)., 2016, (Accepted). Abstract | BibTeX | Tags: Broadcast, MANET, MANET Broadcast @inproceedings{Cordero2016b, title = {Not So Far: Improving Autonomous Content Discovery and Delivery within Mobile Pedestrian Crowds}, author = {Juan Antonio Cordero and Wei Lou}, year = {2016}, date = {2016-08-01}, publisher = {Proceedings of the 25th International Conference on Computer Communication and Networks (ICCCN 2016).}, abstract = {The explosion of traffic demands in the edge of the Internet, mostly by mobile users, is putting under pressure current networking infrastructure. This is particularly acute when huge amounts of users and active wireless devices gather in reduced geographical spaces, increasing the risk of exceeding planned capacity of deployed infrastructure. This trend motivates research on mechanisms to offload part of the user injected traffic from the access infrastructure networks and reduce the need of Internet requests and retrievals. This paper concentrates on the ability of mobile meshes to fulfill the requests for contents originated within the mesh, with minimal intervention of the Internet access infrastructure. We propose, discuss and evaluate simple heuristics to improve autonomous content discovery and dissemination within such mobile meshes, characterized by high density and low (pedestrian) mobility, by combining notions already explored in the context of MANET routing: deliberate jittering and autonomous overlay pruning based on link distance. Results over synthetic networks and real mobility traces indicate that proposed mechanisms can be easily deployed and are able to improve efficiency and quality of content request discoveries, by reducing significantly the collisions and increasing the stability of discovered paths in crowded mesh pedestrian networks.}, note = {Accepted}, keywords = {Broadcast, MANET, MANET Broadcast}, pubstate = {published}, tppubtype = {inproceedings} } The explosion of traffic demands in the edge of the Internet, mostly by mobile users, is putting under pressure current networking infrastructure. This is particularly acute when huge amounts of users and active wireless devices gather in reduced geographical spaces, increasing the risk of exceeding planned capacity of deployed infrastructure. This trend motivates research on mechanisms to offload part of the user injected traffic from the access infrastructure networks and reduce the need of Internet requests and retrievals. This paper concentrates on the ability of mobile meshes to fulfill the requests for contents originated within the mesh, with minimal intervention of the Internet access infrastructure. We propose, discuss and evaluate simple heuristics to improve autonomous content discovery and dissemination within such mobile meshes, characterized by high density and low (pedestrian) mobility, by combining notions already explored in the context of MANET routing: deliberate jittering and autonomous overlay pruning based on link distance. Results over synthetic networks and real mobility traces indicate that proposed mechanisms can be easily deployed and are able to improve efficiency and quality of content request discoveries, by reducing significantly the collisions and increasing the stability of discovered paths in crowded mesh pedestrian networks. |
Cordero, Juan Antonio Multi-Path TCP Performance Evaluation in Dual-Homed (Wired/Wireless) Devices Journal Article Journal of Network and Computer Applications , 70 , pp. 131-139, 2016, ISSN: 1084-8045. Abstract | Links | BibTeX | Tags: Internet Measurements, MP-TCP, Performance Evaluation, Wireless Transport @article{Cordero2016, title = {Multi-Path TCP Performance Evaluation in Dual-Homed (Wired/Wireless) Devices}, author = {Juan Antonio Cordero}, url = {http://www.sciencedirect.com/science/article/pii/S1084804516300819}, doi = {10.1016/j.jnca.2016.05.004}, issn = {1084-8045}, year = {2016}, date = {2016-07-01}, journal = {Journal of Network and Computer Applications }, volume = {70}, pages = {131-139}, abstract = {Multipath TCP is a major extension of TCP, designed for leveraging the increasing availability of multiple interfaces in end hosts, on one side, and the existence of diverse Internet paths between hosts, on the other. This paper proposes a measurement methodology and provides a first evaluation, based on real Internet experiments, of the user benefit of using MPTCP instead of TCP in devices with multiple wireless/wired networking interfaces. We focus on bandwidth utilization and file transfer delays. Our experiments, on a testbed with two disjoint paths connecting a server and a dual-homed probe, indicate that MPTCP is able, in most cases, to take advantage of additional bandwidth with limited cost in terms of delay, but also show that the MPTCP bandwidth benefit substantially degrades when the interfaces have very different bandwidth capacities.}, keywords = {Internet Measurements, MP-TCP, Performance Evaluation, Wireless Transport}, pubstate = {published}, tppubtype = {article} } Multipath TCP is a major extension of TCP, designed for leveraging the increasing availability of multiple interfaces in end hosts, on one side, and the existence of diverse Internet paths between hosts, on the other. This paper proposes a measurement methodology and provides a first evaluation, based on real Internet experiments, of the user benefit of using MPTCP instead of TCP in devices with multiple wireless/wired networking interfaces. We focus on bandwidth utilization and file transfer delays. Our experiments, on a testbed with two disjoint paths connecting a server and a dual-homed probe, indicate that MPTCP is able, in most cases, to take advantage of additional bandwidth with limited cost in terms of delay, but also show that the MPTCP bandwidth benefit substantially degrades when the interfaces have very different bandwidth capacities. |
Jin, Kaiwan; Pfister, Pierre; Yi, Jiazi Distributed Node Consensus Protocol: Analysis, Evaluation and Performance Inproceedings Proceedings of the IEEE International Conference on Communications (ICC) 2016, 2016. Abstract | Links | BibTeX | Tags: Chaire Cisco, DNCP, Homenet, MESH @inproceedings{Jin2016, title = {Distributed Node Consensus Protocol: Analysis, Evaluation and Performance}, author = {Kaiwan Jin and Pierre Pfister and Jiazi Yi}, doi = {10.1109/ICC. 2016.7510939}, year = {2016}, date = {2016-05-23}, publisher = {Proceedings of the IEEE International Conference on Communications (ICC) 2016}, abstract = {Abstract—This paper analyzes and evaluates the Distributed Node Consensus Protocol (DNCP), a state synchronization mech- anism developed by the IETF Homenet working group. DNCP enables network function automation for home networks, which are growing in size and complexity. The basic mechanisms of DNCP are studied in this paper, including the state abstraction, synchronization process and keep-alive mechanism. The over- head is analyzed in single-link topology type. To evaluate the performance of DNCP in more complex scenarios, a reference implementation of DNCP is integrated into ns3 simulator. The convergence time and transmission overhead in various topology types are measured. Based on the obtained results, the correctness of DNCP is verified, and the behavior of DNCP can be concluded.}, keywords = {Chaire Cisco, DNCP, Homenet, MESH}, pubstate = {published}, tppubtype = {inproceedings} } Abstract—This paper analyzes and evaluates the Distributed Node Consensus Protocol (DNCP), a state synchronization mech- anism developed by the IETF Homenet working group. DNCP enables network function automation for home networks, which are growing in size and complexity. The basic mechanisms of DNCP are studied in this paper, including the state abstraction, synchronization process and keep-alive mechanism. The over- head is analyzed in single-link topology type. To evaluate the performance of DNCP in more complex scenarios, a reference implementation of DNCP is integrated into ns3 simulator. The convergence time and transmission overhead in various topology types are measured. Based on the obtained results, the correctness of DNCP is verified, and the behavior of DNCP can be concluded. |
Herberg, Ulrich; Cole, Robert G; Chakeres, Ian; Clausen, Thomas RFC7939: Definition of Managed Objects for the Neighborhood Discovery Protocol Miscellaneous IETF - Proposed Standard RFC 7939, 2016, ISSN: 2070-1721. Abstract | Links | BibTeX | Tags: Ad-Hoc, MANET, MESH, MIB, Network Management, NHDP, OLSRv2, RFC @misc{RFC7939, title = {RFC7939: Definition of Managed Objects for the Neighborhood Discovery Protocol}, author = {Ulrich Herberg and Robert G. Cole and Ian Chakeres and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2016/09/RFC7939.pdf}, doi = {10.17487/rfc7939}, issn = {2070-1721}, year = {2016}, date = {2016-01-01}, number = {7939}, publisher = {RFC Editor}, series = {Request for Comments}, abstract = {This document replaces RFC 6779; it contains revisions and extensions to the original document. It defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes objects for configuring parameters of the Neighborhood Discovery Protocol (NHDP) process on a router. The extensions described in this document add objects and values to support the NHDP optimization specified in RFC 7466. The MIB module defined in this document, denoted NHDP-MIB, also reports state, performance information, and notifications about NHDP. This additional state and performance information is useful to troubleshoot problems and performance issues during neighbor discovery.}, howpublished = {IETF - Proposed Standard RFC 7939}, keywords = {Ad-Hoc, MANET, MESH, MIB, Network Management, NHDP, OLSRv2, RFC}, pubstate = {published}, tppubtype = {misc} } This document replaces RFC 6779; it contains revisions and extensions to the original document. It defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes objects for configuring parameters of the Neighborhood Discovery Protocol (NHDP) process on a router. The extensions described in this document add objects and values to support the NHDP optimization specified in RFC 7466. The MIB module defined in this document, denoted NHDP-MIB, also reports state, performance information, and notifications about NHDP. This additional state and performance information is useful to troubleshoot problems and performance issues during neighbor discovery. |
2015 |
Dearlove, Christopher; Clausen, Thomas RFC7722: Multi-Topology Extension for the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous IETF - Experimental RFC 7722, 2015, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7722). Abstract | Links | BibTeX | Tags: Ad-Hoc, IETF, MANET, MESH, OLSRv2, RFC @misc{RFC7722, title = {RFC7722: Multi-Topology Extension for the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Christopher Dearlove and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7722.txt.pdf}, doi = {10.17487/RFC7722}, issn = {2070-1721}, year = {2015}, date = {2015-12-31}, abstract = {This specification describes an extension to the Optimized Link State Routing Protocol version 2 (OLSRv2) to support multiple routing topologies, while retaining interoperability with OLSRv2 routers that do not implement this extension. This specification updates RFCs 7188 and 7631 by modifying and extending TLV registries and descriptions.}, howpublished = {IETF - Experimental RFC 7722}, note = {http://tools.ietf.org/html/rfc7722}, keywords = {Ad-Hoc, IETF, MANET, MESH, OLSRv2, RFC}, pubstate = {published}, tppubtype = {misc} } This specification describes an extension to the Optimized Link State Routing Protocol version 2 (OLSRv2) to support multiple routing topologies, while retaining interoperability with OLSRv2 routers that do not implement this extension. This specification updates RFCs 7188 and 7631 by modifying and extending TLV registries and descriptions. |
Toubaline, Sonia; Poirion, Pierre-Louis; D’Ambrosio, Claudia; Liberti, Leo Observing the State of a Smart Grid Using Bilevel Programming Inproceedings In Proceeding of the 9th Annual International Conference on Combinatorial Optimization and Applications (COCOA'15),, LNCS 9486, 364-376, 2015. Abstract | Links | BibTeX | Tags: Optimisation, Smart Grid, SOGRID @inproceedings{Toubaline2015, title = {Observing the State of a Smart Grid Using Bilevel Programming}, author = {Sonia Toubaline and Pierre-Louis Poirion and Claudia D’Ambrosio and Leo Liberti}, url = {https://epizeuxis.net/site/wp-content/uploads/2016/01/cocoa15a.pdf}, year = {2015}, date = {2015-12-18}, booktitle = {In Proceeding of the 9th Annual International Conference on Combinatorial Optimization and Applications (COCOA'15),}, publisher = {LNCS 9486, 364-376}, abstract = {Monitoring an electrical network is an important and chal- lenging task. Phasor measurement units are measurement devices that can be used for a state estimation of this network. In this paper we consider a PMU placement problem without conventional measurements and with zero injection nodes for a full observability of the network. We propose two new approaches to model this problem, which take into ac- count a propagation rule based on Ohm’s and Kirchoff’s law. The natural binary linear programming description models an iterative observability process. We remove the iteration by reformulating its fixed point con- ditions to a bilevel program, which we then further reformulate to a single-level mixed-integer linear program. We also present a bilevel al- gorithm to solve directly the proposed bilevel model. We implemented and tested our models and algorithm: the results show that the bilevel algorithm is better in terms of running time and size of instances which can be solved.}, keywords = {Optimisation, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {inproceedings} } Monitoring an electrical network is an important and chal- lenging task. Phasor measurement units are measurement devices that can be used for a state estimation of this network. In this paper we consider a PMU placement problem without conventional measurements and with zero injection nodes for a full observability of the network. We propose two new approaches to model this problem, which take into ac- count a propagation rule based on Ohm’s and Kirchoff’s law. The natural binary linear programming description models an iterative observability process. We remove the iteration by reformulating its fixed point con- ditions to a bilevel program, which we then further reformulate to a single-level mixed-integer linear program. We also present a bilevel al- gorithm to solve directly the proposed bilevel model. We implemented and tested our models and algorithm: the results show that the bilevel algorithm is better in terms of running time and size of instances which can be solved. |
Clausen, Thomas; Dearlove, Christopher RFC7631 – TLV Naming in the Mobile Ad Hoc Network (MANET) Generalized Packet/Message Format Miscellaneous IETF - Proposed Standard RFC 7631, 2015, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7631). Abstract | Links | BibTeX | Tags: Ad-Hoc, IETF, MANET, MESH, OLSRv2, RFC, Standard @misc{RFC7631, title = {RFC7631 – TLV Naming in the Mobile Ad Hoc Network (MANET) Generalized Packet/Message Format}, author = {Thomas Clausen and Christopher Dearlove}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7631.txt.pdf}, doi = {10.17487/RFC7631}, issn = {2070-1721}, year = {2015}, date = {2015-09-01}, abstract = {This document reorganizes the naming of already-allocated TLV (type-length-value) types and type extensions in the "Mobile Ad hoc NETwork (MANET) Parameters" registries defined by RFC 5444 to use names appropriately. It has no consequences in terms of any protocol implementation. This document also updates the Expert Review guidelines in RFC 5444, so as to establish a policy for consistent naming of future TLV type and type extension allocations. It makes no other changes to RFC 5444.}, howpublished = {IETF - Proposed Standard RFC 7631}, note = {http://tools.ietf.org/html/rfc7631}, keywords = {Ad-Hoc, IETF, MANET, MESH, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } This document reorganizes the naming of already-allocated TLV (type-length-value) types and type extensions in the "Mobile Ad hoc NETwork (MANET) Parameters" registries defined by RFC 5444 to use names appropriately. It has no consequences in terms of any protocol implementation. This document also updates the Expert Review guidelines in RFC 5444, so as to establish a policy for consistent naming of future TLV type and type extension allocations. It makes no other changes to RFC 5444. |
Yi, Jiazi; Clausen, Thomas; Herberg, Ulrich Depth-First Forwarding for Unreliable Networks: Extensions and Application Journal Article IEEE Internet of Things Journal, 2015 (06), 2015. Abstract | Links | BibTeX | Tags: DFF, LLN, LOADng, MESH, Smart Grid, SOGRID @article{Yi2015, title = {Depth-First Forwarding for Unreliable Networks: Extensions and Application}, author = {Jiazi Yi and Thomas Clausen and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2015-IEEE-Internet-of-Things-Journal-Depth-First-Forwarding-for-Unreliable-Networks-Extensions-and-Applications.pdf}, doi = {10.1109/JIOT.2015.2409892}, year = {2015}, date = {2015-05-25}, journal = {IEEE Internet of Things Journal}, volume = {2015}, number = {06}, abstract = {his paper introduces extensions and applications of depth-first forwarding (DFF)-a data forwarding mechanism for use in unreliable networks such as sensor networks and Mobile Ad hoc NETworks with limited computational power and storage, low-capacity channels, device mobility, etc. Routing protocols for these networks try to balance conflicting requirements of being reactive to topology and channel variation while also being frugal in resource requirements-but when the underlying topology changes, routing protocols require time to re converge, during which data delivery failure may occur. DFF was developed to alleviate this situation: it reacts rapidly to local data delivery failures and attempts to successfully deliver data while giving a routing protocol time to recover from such a failure. An extension of DFF, denoted as DFF++, is proposed in this paper, in order to optimize the performance of DFF by way of introducing a more efficient search ordering. This paper also studies the applicability of DFF to three major routing protocols for the Internet of Things (IoT), including the Lightweight On-demand Ad hoc Distance-vector Routing Protocol-Next Generation (LOADng), the optimized link state routing protocol version 2 (OLSRv2), and the IPv6 routing protocol for low-power and lossy networks (RPL), and presents the performance of these protocols, with and without DFF, in lossy and unreliable networks.}, keywords = {DFF, LLN, LOADng, MESH, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {article} } his paper introduces extensions and applications of depth-first forwarding (DFF)-a data forwarding mechanism for use in unreliable networks such as sensor networks and Mobile Ad hoc NETworks with limited computational power and storage, low-capacity channels, device mobility, etc. Routing protocols for these networks try to balance conflicting requirements of being reactive to topology and channel variation while also being frugal in resource requirements-but when the underlying topology changes, routing protocols require time to re converge, during which data delivery failure may occur. DFF was developed to alleviate this situation: it reacts rapidly to local data delivery failures and attempts to successfully deliver data while giving a routing protocol time to recover from such a failure. An extension of DFF, denoted as DFF++, is proposed in this paper, in order to optimize the performance of DFF by way of introducing a more efficient search ordering. This paper also studies the applicability of DFF to three major routing protocols for the Internet of Things (IoT), including the Lightweight On-demand Ad hoc Distance-vector Routing Protocol-Next Generation (LOADng), the optimized link state routing protocol version 2 (OLSRv2), and the IPv6 routing protocol for low-power and lossy networks (RPL), and presents the performance of these protocols, with and without DFF, in lossy and unreliable networks. |
Jiménez, Yury Andrea; Cordero, Juan Antonio; Cervelló-Pastor, Cristina Measuring Robustness of SDN Control Layers Inproceedings Proceedings of the 14th IFIP/IEEE International Symposium on Integrated Network Management (IM 2015), 2015. Abstract | Links | BibTeX | Tags: Autoconfiguration @inproceedings{Jiménez2015, title = {Measuring Robustness of SDN Control Layers}, author = {Yury Andrea Jiménez and Juan Antonio Cordero and Cristina Cervelló-Pastor}, url = {http://dl.ifip.org/db/conf/im/im2015p/137468.pdf}, year = {2015}, date = {2015-05-01}, publisher = {Proceedings of the 14th IFIP/IEEE International Symposium on Integrated Network Management (IM 2015)}, abstract = {The controller placement problem remains a key aspect of Software Defined Networking (SDN). The selection of a suboptimal controller may impact severely the performance of the control layer and, in consequence, cause a substantial degradation in the data layer. Different approaches for controller placement have been proposed with various objectives in mind, but most of them do not consider the characteristics of the resulting control layer in terms of robustness. In this paper we propose and formalize a complete metric for estimating robustness of a SDN control layer, and we evaluate two heuristics for controller selection and control layer construction: Fast Failover and a simplified version of k-Critical. The results of the performed evaluation indicate that the control layer topology induced by k-Critical is less prone to failures, more robust and more homogenous than those computed by Fast Failover.}, keywords = {Autoconfiguration}, pubstate = {published}, tppubtype = {inproceedings} } The controller placement problem remains a key aspect of Software Defined Networking (SDN). The selection of a suboptimal controller may impact severely the performance of the control layer and, in consequence, cause a substantial degradation in the data layer. Different approaches for controller placement have been proposed with various objectives in mind, but most of them do not consider the characteristics of the resulting control layer in terms of robustness. In this paper we propose and formalize a complete metric for estimating robustness of a SDN control layer, and we evaluate two heuristics for controller selection and control layer construction: Fast Failover and a simplified version of k-Critical. The results of the performed evaluation indicate that the control layer topology induced by k-Critical is less prone to failures, more robust and more homogenous than those computed by Fast Failover. |
Dearlove, Christopher; Clausen, Thomas RFC7466: An Optimization for the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) Miscellaneous IETF - Proposed Standard RFC 7466, 2015, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7466). Abstract | Links | BibTeX | Tags: Ad-Hoc, IETF, MANET, MESH, NHDP, OLSRv2, RFC, Standard @misc{RFC7466, title = {RFC7466: An Optimization for the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP)}, author = {Christopher Dearlove and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7466.pdf}, doi = {10.17487/RFC7466}, issn = {2070-1721}, year = {2015}, date = {2015-03-01}, abstract = {The link quality mechanism of the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) enables "ignoring" some 1-hop neighbors if the measured link quality from that 1-hop neighbor is below an acceptable threshold while still retaining the corresponding link information as acquired from the HELLO message exchange. This allows immediate reinstatement of the 1-hop neighbor if the link quality later improves sufficiently. NHDP also collects information about symmetric 2-hop neighbors. However, it specifies that if a link from a symmetric 1-hop neighbor ceases being symmetric, including while "ignored" (as described above), then corresponding symmetric 2-hop neighbors are removed. This may lead to symmetric 2-hop neighborhood information being permanently removed (until further HELLO messages are received) if the link quality of a symmetric 1-hop neighbor drops below the acceptable threshold, even if only for a moment. This specification updates RFC 6130 "Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP)" and RFC 7181 "The Optimized Link State Routing Protocol Version 2 (OLSRv2)" to permit, as an option, retaining, but ignoring, symmetric 2-hop information when the link quality from the corresponding 1-hop neighbor drops below the acceptable threshold. This allows immediate reinstatement of the symmetric 2-hop neighbor if the link quality later improves sufficiently, thus making the symmetric 2-hop neighborhood more "robust".}, howpublished = {IETF - Proposed Standard RFC 7466}, note = {http://tools.ietf.org/html/rfc7466}, keywords = {Ad-Hoc, IETF, MANET, MESH, NHDP, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } The link quality mechanism of the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) enables "ignoring" some 1-hop neighbors if the measured link quality from that 1-hop neighbor is below an acceptable threshold while still retaining the corresponding link information as acquired from the HELLO message exchange. This allows immediate reinstatement of the 1-hop neighbor if the link quality later improves sufficiently. NHDP also collects information about symmetric 2-hop neighbors. However, it specifies that if a link from a symmetric 1-hop neighbor ceases being symmetric, including while "ignored" (as described above), then corresponding symmetric 2-hop neighbors are removed. This may lead to symmetric 2-hop neighborhood information being permanently removed (until further HELLO messages are received) if the link quality of a symmetric 1-hop neighbor drops below the acceptable threshold, even if only for a moment. This specification updates RFC 6130 "Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP)" and RFC 7181 "The Optimized Link State Routing Protocol Version 2 (OLSRv2)" to permit, as an option, retaining, but ignoring, symmetric 2-hop information when the link quality from the corresponding 1-hop neighbor drops below the acceptable threshold. This allows immediate reinstatement of the symmetric 2-hop neighbor if the link quality later improves sufficiently, thus making the symmetric 2-hop neighborhood more "robust". |
Cordero, Juan Antonio Information Mediation in the Internet: Evolution, Trends and Threats Miscellaneous Dígitos – Revista de Comunicación Digital, no. 1, pp. 13-36, University of Valencia, 2015, ISSN: 2444-0132, (In Spanish). Abstract | Links | BibTeX | Tags: Scientific dissemination @misc{Cordero2015, title = {Information Mediation in the Internet: Evolution, Trends and Threats}, author = {Juan Antonio Cordero}, url = {https://www.academia.edu/9624590/La_mediaci%C3%B3n_de_la_informaci%C3%B3n_en_Internet_evoluci%C3%B3n_tendencias_y_riesgos}, issn = {2444-0132}, year = {2015}, date = {2015-01-01}, journal = {Dígitos – Revista de Comunicación Digital}, volume = {1}, number = {1}, pages = {13-36}, abstract = {The expansion of the Internet is significantly modifying both the structure and dynamics of the news media, especially in those societies where it is more present. In a short time, the Internet has become a relevant channel for information flow, fact checking, and public discussion, as well as an increasingly important space for public opinion formation. More recently, it has also been used a means for social mobilization and political action. Expectations and hopes around the Internet have been extremely high. In short, the“Internetpromise”hasconsistedonproviding free information access and non-mediated communication, thereby dramatically reducing the power of hegemonic media. However, ongoingtransformations,especiallythoserelated to the so-called “content-centric Internet”, rather suggest that its evolution may point to the opposite direction, towards a more persuasive, increasingly mediated network, in which the power of the news media would increase —rather than decrease—, and would therefore provide them with a more prominent role in public opinion formation process. This paper examines some of the most relevant technological changes that are taking place in the Internet and discusses their possible impact on the autonomy and freedom of final users, on the one hand, and the ideal of free information access and direct and non-mediated communication that was at the core of the Internet original architecture, on the other. }, howpublished = {Dígitos – Revista de Comunicación Digital, no. 1, pp. 13-36, University of Valencia}, note = {In Spanish}, keywords = {Scientific dissemination}, pubstate = {published}, tppubtype = {misc} } The expansion of the Internet is significantly modifying both the structure and dynamics of the news media, especially in those societies where it is more present. In a short time, the Internet has become a relevant channel for information flow, fact checking, and public discussion, as well as an increasingly important space for public opinion formation. More recently, it has also been used a means for social mobilization and political action. Expectations and hopes around the Internet have been extremely high. In short, the“Internetpromise”hasconsistedonproviding free information access and non-mediated communication, thereby dramatically reducing the power of hegemonic media. However, ongoingtransformations,especiallythoserelated to the so-called “content-centric Internet”, rather suggest that its evolution may point to the opposite direction, towards a more persuasive, increasingly mediated network, in which the power of the news media would increase —rather than decrease—, and would therefore provide them with a more prominent role in public opinion formation process. This paper examines some of the most relevant technological changes that are taking place in the Internet and discusses their possible impact on the autonomy and freedom of final users, on the one hand, and the ideal of free information access and direct and non-mediated communication that was at the core of the Internet original architecture, on the other. |
Dearlove, Christopher; Clausen, Thomas H Multi-Topology Extension for the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous RFC 7722, 2015. Abstract | Links | BibTeX | Tags: @misc{RFC7722b, title = {Multi-Topology Extension for the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Christopher Dearlove and Thomas H Clausen}, url = {https://rfc-editor.org/rfc/rfc7722.txt}, doi = {10.17487/RFC7722}, year = {2015}, date = {2015-01-01}, number = {7722}, publisher = {RFC Editor}, series = {Request for Comments}, abstract = {This specification describes an extension to the Optimized Link State Routing Protocol version 2 (OLSRv2) to support multiple routing topologies, while retaining interoperability with OLSRv2 routers that do not implement this extension.}, howpublished = {RFC 7722}, keywords = {}, pubstate = {published}, tppubtype = {misc} } This specification describes an extension to the Optimized Link State Routing Protocol version 2 (OLSRv2) to support multiple routing topologies, while retaining interoperability with OLSRv2 routers that do not implement this extension. |
2014 |
Cordero, Juan Antonio; Bonaventure, Olivier Understanding the topological properties of Internet traffic: a view from the edge Inproceedings Proceedings of the IFIP Networking 2014 Conference, 2014. Abstract | Links | BibTeX | Tags: Internet Measurements @inproceedings{Cordero2014, title = {Understanding the topological properties of Internet traffic: a view from the edge}, author = {Juan Antonio Cordero and Olivier Bonaventure}, url = {https://www.researchgate.net/publication/263584074_Understanding_the_topological_properties_of_Internet_traffic_A_view_from_the_edge}, year = {2014}, date = {2014-06-01}, publisher = {Proceedings of the IFIP Networking 2014 Conference}, abstract = {Traffic between an edge network and the rest of the Internet can be represented as a dynamic loop-free graph. Understanding in depth the dynamics in time and space (spatial structure, topological breadth, destination persistency, traffic dominating paths) of this graph provides significant insight on the Internet internal architecture and capabilities. This paper analyzes interdomain traffic from a large campus network based on one month by way of Netflow measurements. Our analysis reveals the topological properties and structure of the traffic graph (breadth, depth, volume), the stability of contacted destinations and the relationship between their popularity and their path length. Based on the observed traffic, we explore the suitability of a simple mathematical model to describe the structure of the outgoing traffic graph.}, keywords = {Internet Measurements}, pubstate = {published}, tppubtype = {inproceedings} } Traffic between an edge network and the rest of the Internet can be represented as a dynamic loop-free graph. Understanding in depth the dynamics in time and space (spatial structure, topological breadth, destination persistency, traffic dominating paths) of this graph provides significant insight on the Internet internal architecture and capabilities. This paper analyzes interdomain traffic from a large campus network based on one month by way of Netflow measurements. Our analysis reveals the topological properties and structure of the traffic graph (breadth, depth, volume), the stability of contacted destinations and the relationship between their popularity and their path length. Based on the observed traffic, we explore the suitability of a simple mathematical model to describe the structure of the outgoing traffic graph. |
Clausen, Thomas; Dearlove, Christopher; Jacquet, Philippe; Herberg, Ulrich RFC7181: The Optimized Link State Routing Protocol Version 2 Miscellaneous IETF - Proposed Standard RFC 7681, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7181). Abstract | Links | BibTeX | Tags: IETF, MANET, MESH, OLSRv2, RFC, Standard @misc{RFC7181, title = {RFC7181: The Optimized Link State Routing Protocol Version 2}, author = {Thomas Clausen and Christopher Dearlove and Philippe Jacquet and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7181.pdf}, doi = {10.17487/RFC7181}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This specification describes version 2 of the Optimized Link State Routing Protocol (OLSRv2) for Mobile Ad Hoc Networks (MANETs).}, howpublished = {IETF - Proposed Standard RFC 7681}, note = {http://tools.ietf.org/html/rfc7181}, keywords = {IETF, MANET, MESH, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } This specification describes version 2 of the Optimized Link State Routing Protocol (OLSRv2) for Mobile Ad Hoc Networks (MANETs). |
Herberg, Ulrich; Clausen, Thomas; Dearlove, Christopher RFC7182: Integrity Check Value and Timestamp TLV Definitions for Mobile Ad Hoc Networks (MANETs) Miscellaneous IETF - Proposed Standard RFC 7182, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7182). Abstract | Links | BibTeX | Tags: Ad-Hoc, IETF, MANET, OLSRv2, RFC, Standard @misc{RFC7182, title = {RFC7182: Integrity Check Value and Timestamp TLV Definitions for Mobile Ad Hoc Networks (MANETs)}, author = {Ulrich Herberg and Thomas Clausen and Christopher Dearlove}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7182.pdf}, doi = {10.17487/RFC7182}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This document revises, extends, and replaces RFC 6622. It describes general and flexible TLVs for representing cryptographic Integrity Check Values (ICVs) and timestamps, using the generalized Mobile Ad Hoc Network (MANET) packet/message format defined in RFC 5444. It defines two Packet TLVs, two Message TLVs, and two Address Block TLVs for affixing ICVs and timestamps to a packet, a message, and one or more addresses, respectively.}, howpublished = {IETF - Proposed Standard RFC 7182}, note = {http://tools.ietf.org/html/rfc7182}, keywords = {Ad-Hoc, IETF, MANET, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } This document revises, extends, and replaces RFC 6622. It describes general and flexible TLVs for representing cryptographic Integrity Check Values (ICVs) and timestamps, using the generalized Mobile Ad Hoc Network (MANET) packet/message format defined in RFC 5444. It defines two Packet TLVs, two Message TLVs, and two Address Block TLVs for affixing ICVs and timestamps to a packet, a message, and one or more addresses, respectively. |
Herberg, Ulrich; Dearlove, Christopher; Clausen, Thomas IETF - Proposed Standard RFC 7183, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7183). Abstract | Links | BibTeX | Tags: Ad-Hoc, IETF, MANET, NHDP, OLSR Security, OLSRv2, RFC, Security @misc{RFC7183, title = {RFC7183: Integrity Protection for the Neighborhood Discovery Protocol (NHDP) and Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Ulrich Herberg and Christopher Dearlove and Thomas Clausen}, url = {https://epizeuxis.net/site/wp-content/uploads/2015/12/rfc7183.pdf}, doi = {10.17487/RFC7183}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This document specifies integrity and replay protection for the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) and the Optimized Link State Routing Protocol version 2 (OLSRv2). This protection is achieved by using an HMAC-SHA-256 Integrity Check Value (ICV) TLV and a Timestamp TLV based on Portable Operating System Interface (POSIX) time. The mechanism in this specification can also be used for other protocols that use the generalized packet/message format described in RFC 5444. This document updates RFC 6130 and RFC 7181 by mandating the implementation of this integrity and replay protection in NHDP and OLSRv2.}, howpublished = {IETF - Proposed Standard RFC 7183}, note = {http://tools.ietf.org/html/rfc7183}, keywords = {Ad-Hoc, IETF, MANET, NHDP, OLSR Security, OLSRv2, RFC, Security}, pubstate = {published}, tppubtype = {misc} } This document specifies integrity and replay protection for the Mobile Ad Hoc Network (MANET) Neighborhood Discovery Protocol (NHDP) and the Optimized Link State Routing Protocol version 2 (OLSRv2). This protection is achieved by using an HMAC-SHA-256 Integrity Check Value (ICV) TLV and a Timestamp TLV based on Portable Operating System Interface (POSIX) time. The mechanism in this specification can also be used for other protocols that use the generalized packet/message format described in RFC 5444. This document updates RFC 6130 and RFC 7181 by mandating the implementation of this integrity and replay protection in NHDP and OLSRv2. |
Herberg, Ulrich; Cole, Robert G; Clausen, Thomas RFC7184: Definition of Managed Objects for the Optimized Link State Routing Protocol Version 2 Miscellaneous IETF - Proposed Standard RFC 7184, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7184). Abstract | Links | BibTeX | Tags: Ad-Hoc, IETF, MANET, MESH, Network Management, OLSRv2, RFC, Standard @misc{RFC7184, title = {RFC7184: Definition of Managed Objects for the Optimized Link State Routing Protocol Version 2}, author = {Ulrich Herberg and Robert G. Cole and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7184.pdf}, doi = {10.17487/RFC7184}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This document defines the Management Information Base (MIB) module for configuring and managing the Optimized Link State Routing Protocol version 2 (OLSRv2). The OLSRv2-MIB module is structured into configuration information, state information, performance information, and notifications. This additional state and performance information is useful for troubleshooting problems and performance issues of the routing protocol. Two levels of compliance allow this MIB module to be deployed on constrained routers.}, howpublished = {IETF - Proposed Standard RFC 7184}, note = {http://tools.ietf.org/html/rfc7184}, keywords = {Ad-Hoc, IETF, MANET, MESH, Network Management, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } This document defines the Management Information Base (MIB) module for configuring and managing the Optimized Link State Routing Protocol version 2 (OLSRv2). The OLSRv2-MIB module is structured into configuration information, state information, performance information, and notifications. This additional state and performance information is useful for troubleshooting problems and performance issues of the routing protocol. Two levels of compliance allow this MIB module to be deployed on constrained routers. |
Dearlove, Christopher; Clausen, Thomas; Jacquet, Philippe RFC7185: Rationale for the Use of Link Metrics in the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous IETF - Informational RFC 7185, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7185). Abstract | Links | BibTeX | Tags: IETF, MANET, MESH, Metrics, OLSRv2, RFC, Standard @misc{RFC7185, title = {RFC7185: Rationale for the Use of Link Metrics in the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Christopher Dearlove and Thomas Clausen and Philippe Jacquet}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7185.pdf}, doi = {10.17487/RFC7185}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {The Optimized Link State Routing Protocol version 2 (OLSRv2) includes the ability to assign metrics to links and to use those metrics to allow routing by other than minimum hop count routes. This document provides a historic record of the rationale for, and design considerations behind, how link metrics were included in OLSRv2.}, howpublished = {IETF - Informational RFC 7185}, note = {http://tools.ietf.org/html/rfc7185}, keywords = {IETF, MANET, MESH, Metrics, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } The Optimized Link State Routing Protocol version 2 (OLSRv2) includes the ability to assign metrics to links and to use those metrics to allow routing by other than minimum hop count routes. This document provides a historic record of the rationale for, and design considerations behind, how link metrics were included in OLSRv2. |
Yi, Jiazi; Herberg, Ulrich; Clausen, Thomas RFC7186: Security Threats for the Neighborhood Discovery Protocol (NHDP) Miscellaneous IETF - Informational RFC 7186, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7186). Abstract | Links | BibTeX | Tags: IETF, MESH, NHDP, OLSR Security, OLSRv2, RFC, Security, Standard @misc{RFC7186, title = {RFC7186: Security Threats for the Neighborhood Discovery Protocol (NHDP)}, author = {Jiazi Yi and Ulrich Herberg and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7186.pdf}, doi = {10.17487/RFC7186}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This document analyzes common security threats of the Neighborhood Discovery Protocol (NHDP) and describes their potential impacts on Mobile Ad Hoc Network (MANET) routing protocols using NHDP. This document is not intended to propose solutions to the threats described.}, howpublished = {IETF - Informational RFC 7186}, note = {http://tools.ietf.org/html/rfc7186}, keywords = {IETF, MESH, NHDP, OLSR Security, OLSRv2, RFC, Security, Standard}, pubstate = {published}, tppubtype = {misc} } This document analyzes common security threats of the Neighborhood Discovery Protocol (NHDP) and describes their potential impacts on Mobile Ad Hoc Network (MANET) routing protocols using NHDP. This document is not intended to propose solutions to the threats described. |
Dearlove, Christopher; Clausen, Thomas RFC7187: Routing Multipoint Relay Optimization for the Optimized Link State Routing Protocol Version 2 (OLSRv2) Miscellaneous IETF - Proposed Standard RFC 7187, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7187). Abstract | Links | BibTeX | Tags: IETF, MANET, MESH, OLSRv2, RFC, Standard @misc{RFC7187, title = {RFC7187: Routing Multipoint Relay Optimization for the Optimized Link State Routing Protocol Version 2 (OLSRv2)}, author = {Christopher Dearlove and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7187.pdf}, doi = {10.17487/RFC7187}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This specification updates the Optimized Link State Routing Protocol version 2 (OLSRv2) with an optimization to improve the selection of routing multipoint relays. The optimization retains full interoperability between implementations of OLSRv2 with and without this optimization.}, howpublished = {IETF - Proposed Standard RFC 7187}, note = {http://tools.ietf.org/html/rfc7187}, keywords = {IETF, MANET, MESH, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } This specification updates the Optimized Link State Routing Protocol version 2 (OLSRv2) with an optimization to improve the selection of routing multipoint relays. The optimization retains full interoperability between implementations of OLSRv2 with and without this optimization. |
Dearlove, Christopher; Clausen, Thomas IETF - Proposed Standard RFC 7188, 2014, ISSN: 2070-1721, (http://tools.ietf.org/html/rfc7188). Abstract | Links | BibTeX | Tags: IETF, MANET, MESH, NHDP, OLSRv2, RFC, Standard @misc{Clausen2014b, title = {RFC7188: Optimized Link State Routing Protocol Version 2 (OLSRv2) and MANET Neighborhood Discovery Protocol (NHDP) Extension TLVs}, author = {Christopher Dearlove and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/rfc7188.pdf}, doi = {10.17487/RFC7188}, issn = {2070-1721}, year = {2014}, date = {2014-04-01}, abstract = {This specification describes extensions to definitions of TLVs used by the Optimized Link State Routing Protocol version 2 (OLSRv2) and the MANET Neighborhood Discovery Protocol (NHDP) to increase their abilities to accommodate protocol extensions. This document updates RFC 7181 (OLSRv2) and RFC 6130 (NHDP).}, howpublished = {IETF - Proposed Standard RFC 7188}, note = {http://tools.ietf.org/html/rfc7188}, keywords = {IETF, MANET, MESH, NHDP, OLSRv2, RFC, Standard}, pubstate = {published}, tppubtype = {misc} } This specification describes extensions to definitions of TLVs used by the Optimized Link State Routing Protocol version 2 (OLSRv2) and the MANET Neighborhood Discovery Protocol (NHDP) to increase their abilities to accommodate protocol extensions. This document updates RFC 7181 (OLSRv2) and RFC 6130 (NHDP). |
Yi, Jiazi; Clausen, Thomas Collection Tree Extension of Reactive Routing Protocol for Low-Power and Lossy Networks Journal Article Hindawi International Journal of Distributed Sensor Networks, 2014 (Article ID 352421), pp. 12, 2014. Abstract | Links | BibTeX | Tags: LLN, LOADng, MESH, Smart Grid, SOGRID @article{Yi2014, title = {Collection Tree Extension of Reactive Routing Protocol for Low-Power and Lossy Networks}, author = {Jiazi Yi and Thomas Clausen}, editor = {Christos Verikoukis}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2014-Hindawi-International-Journal-of-Distributed-Sensor-Networks-Collection-Tree-Extension-of-LOADng-Protocol-for-Low-power-and-Lossy-Networks.pdf}, doi = {doi:10.1155/2014/352421}, year = {2014}, date = {2014-03-25}, journal = {Hindawi International Journal of Distributed Sensor Networks}, volume = {2014}, number = {Article ID 352421}, pages = {12}, abstract = {This paper proposes an extension to reactive routing protocol, for efficient construction of a collection tree for data acquisition in sensor networks. The Lightweight On-Demand Ad hoc Distance Vector Routing Protocol-Next Generation (LOADng) is a reactive distance vector protocol which is intended for use in mobile ad hoc networks and low-power and lossy networks to build paths between source-destination pairs. In 2013, ITU-T has ratified the recommendation G.9903 Amendment 1, which includes LOADng in a specific normative annex for routing protocol in smart grids. The extension uses the mechanisms from LOADng, imposes minimal overhead and complexity, and enables a deployment to efficiently support “sensor-to-root” traffic, avoiding complications of unidirectional links in the collection tree. The protocol complexity, security, and interoperability are examined in detail. The simulation results show that the extension can effectively improve the efficiency of data acquisition in the network.}, keywords = {LLN, LOADng, MESH, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {article} } This paper proposes an extension to reactive routing protocol, for efficient construction of a collection tree for data acquisition in sensor networks. The Lightweight On-Demand Ad hoc Distance Vector Routing Protocol-Next Generation (LOADng) is a reactive distance vector protocol which is intended for use in mobile ad hoc networks and low-power and lossy networks to build paths between source-destination pairs. In 2013, ITU-T has ratified the recommendation G.9903 Amendment 1, which includes LOADng in a specific normative annex for routing protocol in smart grids. The extension uses the mechanisms from LOADng, imposes minimal overhead and complexity, and enables a deployment to efficiently support “sensor-to-root” traffic, avoiding complications of unidirectional links in the collection tree. The protocol complexity, security, and interoperability are examined in detail. The simulation results show that the extension can effectively improve the efficiency of data acquisition in the network. |
Yi, Jiazi; Clausen, Thomas; Herberg, Ulrich Depth First Forwarding for Low Power and Lossy Networks: Application and Extension Inproceedings Proceedings of IEEE World Forum on Internet of Things WF-IoT 2014, 2014. Abstract | Links | BibTeX | Tags: Constrained Networks, Cross-Layer Design, DFF, LLN, LOADng, MESH, Sensor Networks, Smart Grid, SOGRID @inproceedings{LIX-NET-conference-153, title = {Depth First Forwarding for Low Power and Lossy Networks: Application and Extension}, author = {Jiazi Yi and Thomas Clausen and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2014-IEEE-WF-IoT-Depth-First-Forwarding-for-Low-Power-and-Lossy-Networks-Application-and-Extension.pdf}, doi = {10.1109/WF-IoT.2014.6803211}, year = {2014}, date = {2014-03-01}, publisher = {Proceedings of IEEE World Forum on Internet of Things WF-IoT 2014}, abstract = {Data delivery across a multi-hop low-power and lossy networks (LLNs) is a challenging task: devices participating in such a network have strictly limited computational power and storage, and the communication channels are of low capacity, time-varying and with high loss rates. Consequently, routing protocols finding paths through such a network must be frugal in their control traffic and state requirements, as well as in algorithmic complexity – and even once paths have been found, these may be usable only intermittently, or for a very short time due to changes on the channel. Routing protocols exist for such networks, balancing reactivity to topology and channel variation with frugality in resource requirements. Complementary compo- nent to routing protocols for such LLNs exist, intended not to manage global topology, but to react rapidly to local data delivery failures and (attempt to) successfully deliver data while giving a routing protocol time to recover globally from such a failure. Specifically, this paper studies the “Depth-First Forwarding (DFF) in Unreliable Networks” protocol, standardised within the IETF in June 2013. Moreover, this paper proposes optimisations to that protocol, denoted DFF++, for improved performance and reactivity whilst remaining fully interoperable with DFF as standardised, and incurring neither additional data sets nor protocol signals to be generated.}, keywords = {Constrained Networks, Cross-Layer Design, DFF, LLN, LOADng, MESH, Sensor Networks, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {inproceedings} } Data delivery across a multi-hop low-power and lossy networks (LLNs) is a challenging task: devices participating in such a network have strictly limited computational power and storage, and the communication channels are of low capacity, time-varying and with high loss rates. Consequently, routing protocols finding paths through such a network must be frugal in their control traffic and state requirements, as well as in algorithmic complexity – and even once paths have been found, these may be usable only intermittently, or for a very short time due to changes on the channel. Routing protocols exist for such networks, balancing reactivity to topology and channel variation with frugality in resource requirements. Complementary compo- nent to routing protocols for such LLNs exist, intended not to manage global topology, but to react rapidly to local data delivery failures and (attempt to) successfully deliver data while giving a routing protocol time to recover globally from such a failure. Specifically, this paper studies the “Depth-First Forwarding (DFF) in Unreliable Networks” protocol, standardised within the IETF in June 2013. Moreover, this paper proposes optimisations to that protocol, denoted DFF++, for improved performance and reactivity whilst remaining fully interoperable with DFF as standardised, and incurring neither additional data sets nor protocol signals to be generated. |
Cordero, Juan Antonio; Yi, Jiazi; Clausen, Thomas An Adaptive Jitter Mechanism for Reactive Route Discovery in Sensor Networks Journal Article Sensors, 14 (8), pp. 14440, 2014, ISSN: 1424-8220, (http://www.mdpi.com/1424-8220/14/8/14440). Abstract | Links | BibTeX | Tags: Jitter, LLN, LOADng, MESH, Sensor Networks, Smart Grid @article{s140814440, title = {An Adaptive Jitter Mechanism for Reactive Route Discovery in Sensor Networks}, author = {Juan Antonio Cordero and Jiazi Yi and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2014-MDPI-Sensors-An-Adaptive-Jitter-Mechanism-for-Reactive-Route-Discovery-in-Sensor-Networks.pdf}, doi = {10.3390/s140814440}, issn = {1424-8220}, year = {2014}, date = {2014-01-01}, journal = {Sensors}, volume = {14}, number = {8}, pages = {14440}, abstract = {This paper analyses the impact of jitter when applied to route discovery in reactive (on-demand) routing protocols. In multi-hop non-synchronized wireless networks, jitter—a small, random variation in the timing of message emission—is commonly employed, as a means to avoid collisions of simultaneous transmissions by adjacent routers over the same channel. In a reactive routing protocol for sensor and ad hoc networks, jitter is recommended during the route discovery process, specifically, during the network-wide flooding of route request messages, in order to avoid collisions. Commonly, a simple uniform jitter is recommended. Alas, this is not without drawbacks: when applying uniform jitter to the route discovery process, an effect called delay inversion is observed. This paper, first, studies and quantifies this delay inversion effect. Second, this paper proposes an adaptive jitter mechanism, designed to alleviate the delay inversion effect and thereby to reduce the route discovery overhead and (ultimately) allow the routing protocol to find more optimal paths, as compared to uniform jitter. This paper presents both analytical and simulation studies, showing that the proposed adaptive jitter can effectively decrease the cost of route discovery and increase the path quality.}, note = {http://www.mdpi.com/1424-8220/14/8/14440}, keywords = {Jitter, LLN, LOADng, MESH, Sensor Networks, Smart Grid}, pubstate = {published}, tppubtype = {article} } This paper analyses the impact of jitter when applied to route discovery in reactive (on-demand) routing protocols. In multi-hop non-synchronized wireless networks, jitter—a small, random variation in the timing of message emission—is commonly employed, as a means to avoid collisions of simultaneous transmissions by adjacent routers over the same channel. In a reactive routing protocol for sensor and ad hoc networks, jitter is recommended during the route discovery process, specifically, during the network-wide flooding of route request messages, in order to avoid collisions. Commonly, a simple uniform jitter is recommended. Alas, this is not without drawbacks: when applying uniform jitter to the route discovery process, an effect called delay inversion is observed. This paper, first, studies and quantifies this delay inversion effect. Second, this paper proposes an adaptive jitter mechanism, designed to alleviate the delay inversion effect and thereby to reduce the route discovery overhead and (ultimately) allow the routing protocol to find more optimal paths, as compared to uniform jitter. This paper presents both analytical and simulation studies, showing that the proposed adaptive jitter can effectively decrease the cost of route discovery and increase the path quality. |
Clausen, Thomas; Yi, Jiazi Path Accumulation Extensions for the LOADng Routing Protocol in Sensor Networks Inproceedings Hsu, RobertC.-H.; Wang, Shangguang (Ed.): Internet of Vehicles – Technologies and Services, pp. 150-159, Springer International Publishing, 2014, ISBN: 978-3-319-11166-7. Abstract | Links | BibTeX | Tags: LLN, LOADng, Sensor Networks @inproceedings{Clausen2014, title = {Path Accumulation Extensions for the LOADng Routing Protocol in Sensor Networks}, author = {Thomas Clausen and Jiazi Yi}, editor = {RobertC.-H. Hsu and Shangguang Wang}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2014-IoV-Path-Accumulation-Extensions-for-the-LOADng-Routing-Protocol-in-Sensor-Networks.pdf http://dx.doi.org/10.1007/978-3-319-11167-4_15}, doi = {10.1007/978-3-319-11167-4_15}, isbn = {978-3-319-11166-7}, year = {2014}, date = {2014-01-01}, booktitle = {Internet of Vehicles – Technologies and Services}, volume = {8662}, pages = {150-159}, publisher = {Springer International Publishing}, series = {Lecture Notes in Computer Science}, abstract = {The “Light-weight On-demand Ad-hoc Distance-vector Routing Protocol – Next Generation” (LOADng) is a simple, yet efficient and flexible routing protocol, specifically designed for use in lossy networks with constrained devices. A reactive protocol, LOADng – as a basic mode of operation – offers discovery and maintenance of hop-by-hop routes and imposes a state in intermediate routers proportional to the number of traffic paths served by that intermediate router. This paper offers an extension to LOADng, denoted LOADng-PA (Path Accumulation). LOADng-PA is designed with the motivation of requiring even less state in each intermediate router, and with that state being independent on the number of concurrent traffic flows carried. Another motivation the design of LOADng-PA is one of monitoring and managing networks: providing more detailed topological visibility of traffic paths through the network, for either traffic or network engineering purposes.}, keywords = {LLN, LOADng, Sensor Networks}, pubstate = {published}, tppubtype = {inproceedings} } The “Light-weight On-demand Ad-hoc Distance-vector Routing Protocol – Next Generation” (LOADng) is a simple, yet efficient and flexible routing protocol, specifically designed for use in lossy networks with constrained devices. A reactive protocol, LOADng – as a basic mode of operation – offers discovery and maintenance of hop-by-hop routes and imposes a state in intermediate routers proportional to the number of traffic paths served by that intermediate router. This paper offers an extension to LOADng, denoted LOADng-PA (Path Accumulation). LOADng-PA is designed with the motivation of requiring even less state in each intermediate router, and with that state being independent on the number of concurrent traffic flows carried. Another motivation the design of LOADng-PA is one of monitoring and managing networks: providing more detailed topological visibility of traffic paths through the network, for either traffic or network engineering purposes. |
2013 |
Clausen, Thomas; Yi, Jiazi; Bas, Antonin; Herberg, Ulrich A Depth First Forwarding (DFF) Extension for the LOADng Routing Protocol Inproceedings ASON 2013 Sixth International Workshop on Autonomous Self-Organizing Networks, 2013. Abstract | Links | BibTeX | Tags: Constrained Networks, Cross-Layer Design, DFF, LLN, LOADng, Sensor Networks, Smart Grid, SOGRID @inproceedings{Clausen2013, title = {A Depth First Forwarding (DFF) Extension for the LOADng Routing Protocol}, author = {Thomas Clausen and Jiazi Yi and Antonin Bas and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2013-ASON-A-Depth-First-Forwarding-DFF-Extension-for-the-LOADng-Routing-Protocol.pdf}, doi = {10.1109/CANDAR.2013.72}, year = {2013}, date = {2013-12-01}, publisher = {ASON 2013 Sixth International Workshop on Autonomous Self-Organizing Networks}, abstract = {This paper explores the cooperation between the new standards for “Low Power and Lossy Networks” (LLNs): IETF RFC 6971, denoted “Depth-First Forwarding in Unreliable Networks” (DFF) and the ITU-T standardised routing protocol “LOADng” (Lightweight On-demand ad hoc Distance-vector Routing - next generation). DFF is a data-forwarding mechanism for increasing reliability of data delivery in networks with dynamic topology and lossy links, using a mechanism similar to a “depth-first search” for the destination of a packet. LOADng is a reactive on-demand routing protocol used in LLNs. The purpose of this study is to evaluate the benefit of using DFF conjointly with a routing protocol. To this end, the paper compares the performance of LOADng and LOADng+DFF using Ns2 simulations, showing a 20% end-to-end data delivery ratio increase at expense of expected longer path lengths.}, keywords = {Constrained Networks, Cross-Layer Design, DFF, LLN, LOADng, Sensor Networks, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {inproceedings} } This paper explores the cooperation between the new standards for “Low Power and Lossy Networks” (LLNs): IETF RFC 6971, denoted “Depth-First Forwarding in Unreliable Networks” (DFF) and the ITU-T standardised routing protocol “LOADng” (Lightweight On-demand ad hoc Distance-vector Routing - next generation). DFF is a data-forwarding mechanism for increasing reliability of data delivery in networks with dynamic topology and lossy links, using a mechanism similar to a “depth-first search” for the destination of a packet. LOADng is a reactive on-demand routing protocol used in LLNs. The purpose of this study is to evaluate the benefit of using DFF conjointly with a routing protocol. To this end, the paper compares the performance of LOADng and LOADng+DFF using Ns2 simulations, showing a 20% end-to-end data delivery ratio increase at expense of expected longer path lengths. |
Yi, Jiazi; Clausen, Thomas; Igarashi, Yuichi Evaluation of Routing Protocol for Low Power and Lossy Networks: LOADng and RPL Inproceedings 2013 IEEE Conference on Wireless Sensors, 2013. Abstract | Links | BibTeX | Tags: Constrained Networks, LLN, LOADng, Performance Evaluation, RPL, Sensor Networks, Smart Grid, SOGRID @inproceedings{Clausen2013a, title = {Evaluation of Routing Protocol for Low Power and Lossy Networks: LOADng and RPL}, author = {Jiazi Yi and Thomas Clausen and Yuichi Igarashi}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2013-ICWiSE-Evaluation-of-Routing-Protocol-for-Low-Power-and-Lossy-Networks-LOADng-and-RPL.pdf}, doi = {10.1109/ICWISE.2013.6728773}, year = {2013}, date = {2013-12-01}, publisher = {2013 IEEE Conference on Wireless Sensors}, abstract = {Routing protocol is a critical component of Low- power and Lossy Networks for Smart Grid. The protocols are used for data forwarding, which includes data acquisition, information dissemination, etc. This paper evaluates two main routing protocols used for Low-power and Lossy Networks: RPL and LOADng, to understand their strengths and limitations. Observations are provided based on analysis of specification and experimental experience, regarding the protocol’s routing overhead, traffic pattern, resource requirement, fragmentation, etc. Simulations are further launched to study the performance in different traffic patterns, which include sensor-to-sensor traffic, sensor-to-root traffic and root-to-sensor bidirectional traffic. By evaluating those protocols, the readers could have better under- standing of the protocol applicability, and choose the appropriate protocol for desired applications.}, keywords = {Constrained Networks, LLN, LOADng, Performance Evaluation, RPL, Sensor Networks, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {inproceedings} } Routing protocol is a critical component of Low- power and Lossy Networks for Smart Grid. The protocols are used for data forwarding, which includes data acquisition, information dissemination, etc. This paper evaluates two main routing protocols used for Low-power and Lossy Networks: RPL and LOADng, to understand their strengths and limitations. Observations are provided based on analysis of specification and experimental experience, regarding the protocol’s routing overhead, traffic pattern, resource requirement, fragmentation, etc. Simulations are further launched to study the performance in different traffic patterns, which include sensor-to-sensor traffic, sensor-to-root traffic and root-to-sensor bidirectional traffic. By evaluating those protocols, the readers could have better under- standing of the protocol applicability, and choose the appropriate protocol for desired applications. |
Clausen, Thomas; de Verdiere, Axel Colin; Yi, Jiazi Performance analysis of Trickle as a flooding mechanism Inproceedings IEEE 15th International Conference on Communication Technology, 2013. Abstract | Links | BibTeX | Tags: Constrained Networks, LLN, Performance Evaluation, RPL, Sensor Networks, Trickle @inproceedings{Clausen2013b, title = {Performance analysis of Trickle as a flooding mechanism}, author = {Thomas Clausen and Axel Colin de Verdiere and Jiazi Yi}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2013-ICCT-Performance-analysis-of-Trickle-as-a-flooding-mechanism.pdf}, doi = {http://dx.doi.org/10.1109/ICCT.2013.6820439}, year = {2013}, date = {2013-11-01}, publisher = {IEEE 15th International Conference on Communication Technology}, abstract = {“The Trickle Algorithm” is conceived as an adaptive mechanism for allowing efficient and reliable information sharing among nodes, communicating across a lossy and shared medium. Its basic principle is, for each node, to monitor transmissions from its neighbours, compare what it receives with its cur- rent state, and schedule future transmissions accordingly: if an inconsistency of information is detected, or if few or no neighbours have transmitted consistent information “recently”, the next transmission is scheduled “soon” – and, in case consistent information from a sufficient number of neighbours is received, the next transmission is scheduled to be “later”. Developed originally as a means of distributing firmware updates among sensor devices, this algorithm has found use also for distribution of routing information in the routing protocol RPL, standardised within the IETF for maintaining a routing topology for low-power and lossy networks (LLNs). Its use is also proposed in a protocol for multicast in LLNs, denoted “Multicast Forwarding Using Trickle”. This paper studies the performance of the Trickle algorithm, as it is used in that multicast protocol.}, keywords = {Constrained Networks, LLN, Performance Evaluation, RPL, Sensor Networks, Trickle}, pubstate = {published}, tppubtype = {inproceedings} } “The Trickle Algorithm” is conceived as an adaptive mechanism for allowing efficient and reliable information sharing among nodes, communicating across a lossy and shared medium. Its basic principle is, for each node, to monitor transmissions from its neighbours, compare what it receives with its cur- rent state, and schedule future transmissions accordingly: if an inconsistency of information is detected, or if few or no neighbours have transmitted consistent information “recently”, the next transmission is scheduled “soon” – and, in case consistent information from a sufficient number of neighbours is received, the next transmission is scheduled to be “later”. Developed originally as a means of distributing firmware updates among sensor devices, this algorithm has found use also for distribution of routing information in the routing protocol RPL, standardised within the IETF for maintaining a routing topology for low-power and lossy networks (LLNs). Its use is also proposed in a protocol for multicast in LLNs, denoted “Multicast Forwarding Using Trickle”. This paper studies the performance of the Trickle algorithm, as it is used in that multicast protocol. |
Yi, Jiazi; Cordero, Juan Antonio; Clausen, Thomas Jitter Considerations in On-demand Route Discovery for Mobile Ad Hoc Networks Inproceedings The 16th International Conference on Network-Based Information Systems (NBiS-2013), 2013. Abstract | Links | BibTeX | Tags: Ad-Hoc, Jitter, LOADng, MANET, MESH, Sensor Networks, Smart Grid, SOGRID @inproceedings{Clausen2013g, title = {Jitter Considerations in On-demand Route Discovery for Mobile Ad Hoc Networks}, author = {Jiazi Yi and Juan Antonio Cordero and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2013-NBIS-Jitter-Considerations-in-On-demand-Route-Discovery-for-Mobile-Ad-Hoc-Networks.pdf}, doi = {10.1109/NBiS.2013.28}, year = {2013}, date = {2013-09-01}, publisher = {The 16th International Conference on Network-Based Information Systems (NBiS-2013)}, abstract = {Jittering (a small, random variation in timing of control message emission) is widely used in protocols for wireless communication, in order to avoid simultaneous packet transmis- sions over the same channel by adjacent nodes in the network. Used for both regularly scheduled packets, for event-triggered packets, and for scheduled resets in the network, jittering is a particularly important mechanism when a network event may cause multiple adjacent nodes to react concurrently. Introduced in the proactive MANET routing protocol OLSR, the “LLN On-demand Ad hoc Distance-vector Routing Protocol - Next Generation” (LOADng), a derivative of AODV, is specified so as to also use jitter for flooding Route Request (RREQ) messages during route discovery. This use of jitter in RREQ flooding is, however, not without drawbacks, which are identified and addressed in this paper within the framework of a more general study of jitter mechanisms used for route discovery in reactive routing protocols. The paper studies the behavior of route discovery when using “naive” jitter (simply, delaying RREQ retransmission by a small uniformly distributed random delay), in order to identify and analyze the problems hereof, mostly related to route sub-optimality and excessive control traffic overhead. A Window Jitter mechanism is then proposed to address these issues – with the performance hereof, when compared to “naive” jitter being evaluated by way of modeling, theoretical analysis and experiments. The paper shows that the use of Window Jitter improves indeed the efficiency of route discovery in AODV and overcome the drawbacks identified for “naive” jitter.}, keywords = {Ad-Hoc, Jitter, LOADng, MANET, MESH, Sensor Networks, Smart Grid, SOGRID}, pubstate = {published}, tppubtype = {inproceedings} } Jittering (a small, random variation in timing of control message emission) is widely used in protocols for wireless communication, in order to avoid simultaneous packet transmis- sions over the same channel by adjacent nodes in the network. Used for both regularly scheduled packets, for event-triggered packets, and for scheduled resets in the network, jittering is a particularly important mechanism when a network event may cause multiple adjacent nodes to react concurrently. Introduced in the proactive MANET routing protocol OLSR, the “LLN On-demand Ad hoc Distance-vector Routing Protocol - Next Generation” (LOADng), a derivative of AODV, is specified so as to also use jitter for flooding Route Request (RREQ) messages during route discovery. This use of jitter in RREQ flooding is, however, not without drawbacks, which are identified and addressed in this paper within the framework of a more general study of jitter mechanisms used for route discovery in reactive routing protocols. The paper studies the behavior of route discovery when using “naive” jitter (simply, delaying RREQ retransmission by a small uniformly distributed random delay), in order to identify and analyze the problems hereof, mostly related to route sub-optimality and excessive control traffic overhead. A Window Jitter mechanism is then proposed to address these issues – with the performance hereof, when compared to “naive” jitter being evaluated by way of modeling, theoretical analysis and experiments. The paper shows that the use of Window Jitter improves indeed the efficiency of route discovery in AODV and overcome the drawbacks identified for “naive” jitter. |
Cordero, Juan Antonio; Yi, Jiazi; Clausen, Thomas; Baccelli, Emmanuel Enabling Multihop Communication in Spontaneous Wireless Networks Book Chapter Haddadi, Hamed; Bonaventure, Olivier (Ed.): Recent Advances in Networking, Chapter 9, pp. 413-457, ACM SIGCOMM, 2013. Links | BibTeX | Tags: Ad-Hoc, LLN, LOADng, MANET, MPR, OLSR, OSPF @inbook{Cordero2013, title = {Enabling Multihop Communication in Spontaneous Wireless Networks}, author = {Juan Antonio Cordero and Jiazi Yi and Thomas Clausen and Emmanuel Baccelli}, editor = {Hamed Haddadi and Olivier Bonaventure}, url = {http://sigcomm.org/education/ebook/SIGCOMMeBook2013v1_chapter9.pdf}, year = {2013}, date = {2013-08-01}, booktitle = {Recent Advances in Networking}, pages = {413-457}, publisher = {ACM SIGCOMM}, chapter = {9}, keywords = {Ad-Hoc, LLN, LOADng, MANET, MPR, OLSR, OSPF}, pubstate = {published}, tppubtype = {inbook} } |
Cordero, Juan Antonio A Probabilistic Study of the Delay caused by Jittering in Wireless Flooding Journal Article Wireless Personal Communications, 73 (3), pp. 415-439, 2013, ISSN: 0929-6212. Abstract | Links | BibTeX | Tags: Jitter, MANET Broadcast, Wireless @article{Cordero2013-WPC, title = {A Probabilistic Study of the Delay caused by Jittering in Wireless Flooding}, author = {Juan Antonio Cordero}, url = {http://link.springer.com/article/10.1007%2Fs11277-013-1195-8}, doi = {10.1007/s11277-013-1195-8}, issn = {0929-6212}, year = {2013}, date = {2013-05-01}, journal = {Wireless Personal Communications}, volume = {73}, number = {3}, pages = {415-439}, abstract = {Systematic packet collisions constitute a major problem in wireless flooding, which is a key mechanism for information dissemination in wireless mesh and multi-hop ad hoc networks. Since this cannot be solved only through classic MAC collision avoidance mechanisms, the IETF has proposed and standardized in RFC 5148 jittering techniques to handle it. These techniques are widely used in protocols for wireless communication such as OLSR, AODV or LOAD, and have proven useful for reducing collisions. They lead however some undesirableside effects that may harm substantially the flooding performance. To the best of our knowledge, no research effort has been deployed to understand and analyze these effects. This paper addresses this issue. It motivates and introduces a theoretical model of flooding with jitter in a wireless interface, as specified in RFC 5148, and explores the probabilistic characterization of additional flooding delay caused by jitter. It mostly provides two analytical bounds for the per-interface additional jitter delay. Presented results, which are validated by way of a discrete-event simulation, enable a better understanding of the performance trade-offs (between packet collisions and additional delay, in particular) underlying the use of jitter in wireless flooding.}, keywords = {Jitter, MANET Broadcast, Wireless}, pubstate = {published}, tppubtype = {article} } Systematic packet collisions constitute a major problem in wireless flooding, which is a key mechanism for information dissemination in wireless mesh and multi-hop ad hoc networks. Since this cannot be solved only through classic MAC collision avoidance mechanisms, the IETF has proposed and standardized in RFC 5148 jittering techniques to handle it. These techniques are widely used in protocols for wireless communication such as OLSR, AODV or LOAD, and have proven useful for reducing collisions. They lead however some undesirableside effects that may harm substantially the flooding performance. To the best of our knowledge, no research effort has been deployed to understand and analyze these effects. This paper addresses this issue. It motivates and introduces a theoretical model of flooding with jitter in a wireless interface, as specified in RFC 5148, and explores the probabilistic characterization of additional flooding delay caused by jitter. It mostly provides two analytical bounds for the per-interface additional jitter delay. Presented results, which are validated by way of a discrete-event simulation, enable a better understanding of the performance trade-offs (between packet collisions and additional delay, in particular) underlying the use of jitter in wireless flooding. |
Cordero, Juan Antonio; Yi, Jiazi; Clausen, Thomas Optimization of jitter configuration for reactive route discovery in wireless mesh networks Inproceedings Modeling & Optimization in Mobile, Ad Hoc & Wireless Networks (WiOpt), 2013 11th International Symposium on, 2013, ISBN: 978-1-61284-824-2. Abstract | Links | BibTeX | Tags: Ad-Hoc, Jitter, LLN, LOADng, MANET, MESH, Sensor Networks, Smart Grid @inproceedings{Clausen2013c, title = {Optimization of jitter configuration for reactive route discovery in wireless mesh networks}, author = {Juan Antonio Cordero and Jiazi Yi and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2013-WiOpt-Optimization-of-Jitter-Configuration-for-Reactive-Route-Discovery-in-Wireless-Mesh-Networks.pdf}, isbn = {978-1-61284-824-2}, year = {2013}, date = {2013-05-01}, publisher = {Modeling & Optimization in Mobile, Ad Hoc & Wireless Networks (WiOpt), 2013 11th International Symposium on}, abstract = {Jitter is a small, random variation of timing before message emission that is widely used in non-synchronized wireless communication. It is employed to avoid collisions caused by simultaneous transmissions by adjacent nodes over the same channel. In reactive (on-demand) routing protocols, such as AODV and LOADng, it is recommended to use jitter during the flooding of Route Request messages. This paper analyzes the cost of jitter mechanisms in route discovery of on-demand routing protocols, and examines the drawbacks of the standard and commonly used uniformly distributed jitter. The main studied drawback is denominated delay inversion effect. Two variations on the jitter mechanism --window jitter and adaptive jitter-- are proposed to address this effect, which take the presence and the quality of traversed links into consideration to determine the per-hop forwarding delay. These variations allow to effectively reduce the routing overhead, and increase the quality of the computed paths with respect to the standard uniform jitter mechanism. Simulations are also performed to compare the performance of different jitter settings in various network scenarios.}, keywords = {Ad-Hoc, Jitter, LLN, LOADng, MANET, MESH, Sensor Networks, Smart Grid}, pubstate = {published}, tppubtype = {inproceedings} } Jitter is a small, random variation of timing before message emission that is widely used in non-synchronized wireless communication. It is employed to avoid collisions caused by simultaneous transmissions by adjacent nodes over the same channel. In reactive (on-demand) routing protocols, such as AODV and LOADng, it is recommended to use jitter during the flooding of Route Request messages. This paper analyzes the cost of jitter mechanisms in route discovery of on-demand routing protocols, and examines the drawbacks of the standard and commonly used uniformly distributed jitter. The main studied drawback is denominated delay inversion effect. Two variations on the jitter mechanism --window jitter and adaptive jitter-- are proposed to address this effect, which take the presence and the quality of traversed links into consideration to determine the per-hop forwarding delay. These variations allow to effectively reduce the routing overhead, and increase the quality of the computed paths with respect to the standard uniform jitter mechanism. Simulations are also performed to compare the performance of different jitter settings in various network scenarios. |