Jiazi Yi, PhD
Research Engineer
Jiazi Yi joined the Network Research Group of Ecole Polytechnique in 2010 as a postdoc researcher, and is currently a research engineer in the group. Jiazi got his Ph.D from University of Nantes, in 2010, a M.Sc. in Electronic System from Polytech’Nantes (France), and a M.Sc. in Computer Science, South China University of Technology.
Jiazi's scientific interests include mobile ad hoc networks, smart grid, routing protocols, sensor networks, long range and low power networks, QoS, etc. His PhD thesis focuses on the multi-path routing protocol for ad hoc networks, in which MP-OLSR was proposed. He has published above 30 peer-reviewed publications and co-authored several international standards. He is also one of the main contributors of LOADng routing protocol, which is the default routing mechanism used in G3-PLC for the future smart grid now being deployed in France and allover the world.
Currently he is also teaching/coordinating 3 classes at Ecole Polytechnique: INF474X (Modal-Cybersecurity), INF557 (Introduction to Network Architectures - TD) and INF667C (ACN-M2 Scientific project).
His home page is http://jiaziyi.com
Latest Posts Mentioning Jiazi
Teaser: dr. Jiazi Yi presenting NSx & LoRA – looking promising.
One of our research activites is “quantifying and improving LoRa”, and we’ve published some interesting results in the past on that topic, based on some analytical — and, a lot of experimental — data. We love experimental work, but sometimes…
Read more
Posted in Colleagues, IoT, Jiazi Yi, LoRa, networking, Ns3, Research, Simulation
|
Comments Off on Teaser: dr. Jiazi Yi presenting NSx & LoRA – looking promising.
Use ’em or Lose ’em: On Unidirectional Links in Reactive Routing Protocols
My colleagues Jiazi, Juan, and I, just finished the final editorial bits of process on a new paper “Use ’em or Lose ’em: On Unidirectional Links in Reactive Routing Protocols”, published in Elsevier Ad Hoc Networks – and with the paper…
Read more
Posted in Colleagues, IoT, Jiazi Yi, Juan Antonio Cordero Fuertes, LOADng, Protocol, Research, Routing, Smart Grid, Thomas Clausen
|
Comments Off on Use ’em or Lose ’em: On Unidirectional Links in Reactive Routing Protocols
Yay! Bibliometrics – a 20 citations-in-8-months paper
I have previously written about how while bibliometrics may pretend to be “quantifying impact” of a scientist, they really do not. That said, it made me smile the other morning when I got a Google Scholar alert that our paper…
Read more
Posted in Academic process, Bibliometrics, Chaire Cisco, Colleagues, Jiazi Yi, Master-ACN, Polytechnique, Thomas Clausen
|
Comments Off on Yay! Bibliometrics – a 20 citations-in-8-months paper
Jiazi’s Publications
Ad-Hoc Autoconfiguration Broadcast Chaire Cisco Constrained Networks IETF Jitter LLN LOADng MANET MANET Broadcast MESH MPR Multicast Network Management NHDP OLSR OLSR Security OLSRv2 OSPF OSPF4MANET Performance Evaluation RFC RPL Security Sensor Networks Smart Grid SMF Security SOGRID Standard
2018 |
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. |
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. |
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, 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, 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 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 = {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. |
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 W 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 W. 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. |
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. |
2015 |
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. |
2014 |
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. |
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. |
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. |
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. |
2013 |
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; 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. |
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; 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. |
2012 |
Yi, Jiazi; Clausen, Thomas; Bas, Antonin Smart Route Request for On-demand Route Discovery in Constrained Environments Inproceedings 2012 IEEE International Conference on Wireless Information Technology and Systems, 2012. Abstract | Links | BibTeX | Tags: Constrained Networks, LLN, LOADng, Sensor Networks @inproceedings{Clause2012f, title = {Smart Route Request for On-demand Route Discovery in Constrained Environments}, author = {Jiazi Yi and Thomas Clausen and Antonin Bas}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2012-IEEE-ICWITS-Smart-Route-Request-for-On-demand-Route-Discovery-in-Constrained-Environments.pdf}, doi = {10.1109/ICWITS.2012.6417755}, year = {2012}, date = {2012-11-01}, publisher = {2012 IEEE International Conference on Wireless Information Technology and Systems}, abstract = {A derivative of AODV , denoted LOADng, is proposed for use in very constrained environment, sacrificing a number of features from AODV for the benefit of smaller control messages and simpler processing logic. Among these sacrifices is intermediate route replies. This paper presents an alternative to intermediate router replies, denoted Smart Route Request, which provides an optimization similar to that attainable by intermediate route requests, but without imposing additional processing complexity or additional signaling. A performance study is presented, showing that the use of Smart Route Requests can effectively reduce the control traffic overhead from Route Requests, while retaining the simplicity of LOADng. LOADng with Smart Route Requests effectively reduces control traffic overhead and on-link traffic collisions, and this especially for multipoint-to-point traffic.}, keywords = {Constrained Networks, LLN, LOADng, Sensor Networks}, pubstate = {published}, tppubtype = {inproceedings} } A derivative of AODV , denoted LOADng, is proposed for use in very constrained environment, sacrificing a number of features from AODV for the benefit of smaller control messages and simpler processing logic. Among these sacrifices is intermediate route replies. This paper presents an alternative to intermediate router replies, denoted Smart Route Request, which provides an optimization similar to that attainable by intermediate route requests, but without imposing additional processing complexity or additional signaling. A performance study is presented, showing that the use of Smart Route Requests can effectively reduce the control traffic overhead from Route Requests, while retaining the simplicity of LOADng. LOADng with Smart Route Requests effectively reduces control traffic overhead and on-link traffic collisions, and this especially for multipoint-to-point traffic. |
Bas, Antonin; Yi, Jiazi; Clausen, Thomas Expanding Ring Search for Route Discovery in LOADng Routing Protocol Inproceedings The 1st International Workshop on Smart Technologies for Energy, Information and Communication, 2012. Abstract | Links | BibTeX | Tags: Constrained Networks, LLN, LOADng, Sensor Networks @inproceedings{Bas2012, title = {Expanding Ring Search for Route Discovery in LOADng Routing Protocol}, author = {Antonin Bas and Jiazi Yi and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2012-STEIC-Expanding-Ring-Search-for-Route-Discovery-in-LOADng-Routing-Protocol.pdf}, year = {2012}, date = {2012-10-01}, publisher = {The 1st International Workshop on Smart Technologies for Energy, Information and Communication}, abstract = {LOADng is an on-demand routing protocol, derived from AODV, simplified for use in lossy, low-power and constrained environments, where the ability for devices to communicate is a commodity to their primary function, and where therefore not only the communications channel offers limited capacity, but also the resources available to the device’s communica- tions subsystem are limted. LOADng simplifies AODV in a number of ways, notably the route discovery process by removing intermediate/gratuitous Route Replies – sacrificing that functionality in order to attain smaller control messages and less router state and processing. Alas, this comes at an expense: in some situations, LOADng produces increased control traffic overhead (as com- pared to AODV), and more control messages transmissions means tapping into the device’s limited resources. This paper presents a simple mechanism by which to integrate Expanding Ring flooding into LOADng. The mechanism is described, and the result of simulation studies are presented, showing that both in scenarios with “point-to-point” (any-to-any) traffic and in scenarios with “multipoint-to-point” (all traffic sent to the same destination, as in a data acquisition sensor network) traffic, considerable savings in control traffic overhead can be achieved – without loss in data delivery ratios.}, keywords = {Constrained Networks, LLN, LOADng, Sensor Networks}, pubstate = {published}, tppubtype = {inproceedings} } LOADng is an on-demand routing protocol, derived from AODV, simplified for use in lossy, low-power and constrained environments, where the ability for devices to communicate is a commodity to their primary function, and where therefore not only the communications channel offers limited capacity, but also the resources available to the device’s communica- tions subsystem are limted. LOADng simplifies AODV in a number of ways, notably the route discovery process by removing intermediate/gratuitous Route Replies – sacrificing that functionality in order to attain smaller control messages and less router state and processing. Alas, this comes at an expense: in some situations, LOADng produces increased control traffic overhead (as com- pared to AODV), and more control messages transmissions means tapping into the device’s limited resources. This paper presents a simple mechanism by which to integrate Expanding Ring flooding into LOADng. The mechanism is described, and the result of simulation studies are presented, showing that both in scenarios with “point-to-point” (any-to-any) traffic and in scenarios with “multipoint-to-point” (all traffic sent to the same destination, as in a data acquisition sensor network) traffic, considerable savings in control traffic overhead can be achieved – without loss in data delivery ratios. |
Yi, Jiazi; Clausen, Thomas; de Verdiere, Axel Colin Efficient Data Acquisition in Sensor Networks:Introducing (the) LOADng Collection Tree Protocol Inproceedings IEEE WiCom 2012, The 8th IEEE International Conference on Wireless Communications, Networking and Mobile Computing., 2012. Abstract | Links | BibTeX | Tags: Constrained Networks, LLN, LOADng, Sensor Networks @inproceedings{Clausen2012, title = {Efficient Data Acquisition in Sensor Networks:Introducing (the) LOADng Collection Tree Protocol}, author = {Jiazi Yi and Thomas Clausen and Axel Colin de Verdiere}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2012-IEEE-WiCOM-Efficient-Data-Acquisition-in-Sensor-NetworksIntroducing-the-LOADng-Collection-Tree-Protocol.pdf}, doi = {10.1109/WiCOM.2012.6478508}, year = {2012}, date = {2012-09-01}, publisher = {IEEE WiCom 2012, The 8th IEEE International Conference on Wireless Communications, Networking and Mobile Computing.}, abstract = {This paper proposes an extension to the “LLN On-demand Ad hoc Distance-vector Routing Protocol - Next Generation” (LOADng), for efficient construction of a collection tree for data acquisition in sensor networks. The extension uses the mechanisms from LOADng, imposes minimal overhead and complexity, and enables a deployment to efficiently support both “point-to-point” and “multipoint-to-point” traffic, avoiding complications of uni-directional links in the collection tree. This paper further compares the performance of proposed pro-tocol extension to that of basic LOADng and to the protocol RPL (“IPv6 Routing Protocol for Low power and Lossy Networks”).}, keywords = {Constrained Networks, LLN, LOADng, Sensor Networks}, pubstate = {published}, tppubtype = {inproceedings} } This paper proposes an extension to the “LLN On-demand Ad hoc Distance-vector Routing Protocol - Next Generation” (LOADng), for efficient construction of a collection tree for data acquisition in sensor networks. The extension uses the mechanisms from LOADng, imposes minimal overhead and complexity, and enables a deployment to efficiently support both “point-to-point” and “multipoint-to-point” traffic, avoiding complications of uni-directional links in the collection tree. This paper further compares the performance of proposed pro-tocol extension to that of basic LOADng and to the protocol RPL (“IPv6 Routing Protocol for Low power and Lossy Networks”). |
Yi, Jiazi; Clausen, Thomas The 15th International Conference on Network-Based Information Systems (NBiS-2012), 2012. Abstract | Links | BibTeX | Tags: Ad-Hoc, MANET, MESH, Security, SMF, SMF Security @inproceedings{Yi2012, title = {Vulnerability Analysis of Relay Set Selection Algorithms for the Simplified Multicast Forwarding (SMF) Protocol for Mobile Ad Hoc Networks}, author = {Jiazi Yi and Thomas Clausen}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2012-NBIS-Vulnerability-Analysis-of-Relay-Set-Selection-Algorithms-for-the-Simplified-Multicast-Forwarding-SMF-Protocol-for-Mobile-Ad-Hoc-Networks.pdf}, doi = {10.1109/NBiS.2012.48}, year = {2012}, date = {2012-09-01}, publisher = {The 15th International Conference on Network-Based Information Systems (NBiS-2012)}, abstract = {After more than a decade of research and stan-dardization, Mobile Ad Hoc NETworks (MANET) are finding their place in real-world deployments, such as in community, tactical and vehicular networks. Becoming so present in “the real world” also means that MANETs, and the protocols operating them, are affronted with a more hostile environment, where misconfiguration, eavesdropping, and attacks must be addressed. A first step in addressing MANET security is understanding the vulnerabilities of MANET protocols, and how an attacker can exploit these. This paper studies the Relay Set Selection (RSS) algorithms that are commonly used in multicast routing protocol for MANETs, and which are undergoing standardization as part of the Simplified Multicast Forwarding (SMF) protocol, developed within the Internet Engineering Task Force (IETF). Attack vectors for these different RSS algorithms are described, with the purpose of enabling future development of security solutions.}, keywords = {Ad-Hoc, MANET, MESH, Security, SMF, SMF Security}, pubstate = {published}, tppubtype = {inproceedings} } After more than a decade of research and stan-dardization, Mobile Ad Hoc NETworks (MANET) are finding their place in real-world deployments, such as in community, tactical and vehicular networks. Becoming so present in “the real world” also means that MANETs, and the protocols operating them, are affronted with a more hostile environment, where misconfiguration, eavesdropping, and attacks must be addressed. A first step in addressing MANET security is understanding the vulnerabilities of MANET protocols, and how an attacker can exploit these. This paper studies the Relay Set Selection (RSS) algorithms that are commonly used in multicast routing protocol for MANETs, and which are undergoing standardization as part of the Simplified Multicast Forwarding (SMF) protocol, developed within the Internet Engineering Task Force (IETF). Attack vectors for these different RSS algorithms are described, with the purpose of enabling future development of security solutions. |
Clausen, Thomas; Yi, Jiazi; de Verdiere, Axel Colin LOADng: Towards AODV Version 2 Inproceedings 2012 IEEE 76th Vehicular Technology Conference, 2012. Abstract | Links | BibTeX | Tags: Constrained Networks, LLN, LOADng, MESH, Sensor Networks @inproceedings{Clausen2012b, title = {LOADng: Towards AODV Version 2}, author = {Thomas Clausen and Jiazi Yi and Axel Colin de Verdiere}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2012-IEEE-VTC-LOADng-Towards-AODVv2.pdf}, doi = {10.1109/VTCFall.2012.6399334}, year = {2012}, date = {2012-09-01}, publisher = {2012 IEEE 76th Vehicular Technology Conference}, abstract = {The Ad hoc On-demand Distance-Vector routing protocol (AODV) was published in 2003 by the IETF, as ex- perimental RFC 3561. This routing protocol was one of four routing protocols, developed by the IETF for use in mobile ad hoc networks (MANETs) – with the other being DSR, TBRPF and OLSR. As operational experiences with these protocols accumulated, the IETF set forth on standardization of OLSRv2, a successor to OLSR, and DYMO – with DYMO being the intended successor to DSR and AODV. Alas, while there was traction for and standardization of OLSRv2, interest in, development, standardization, and use of DYMO in MANETs slowly withered. AODV did, however, attract interest for routing in Low-power Lossy Networks (LLNs) due to its limited state requirements. Since 2005, several proposals for simplifying and adapting AODV specifically for LLNs emerged, in 2011 and 2012 with the use of one such adaptation of AODV in the G3-PLC standard for power line communications in smart grids, and with efforts within the IETF emerging towards a single LOADng specification, as next version of AODV. This paper presents this development – from AODV, as specified in RFC3561 – to LOADng. While the basic operation remains unchanged, LOADng presents simplifications, and additional features and flexibilities are introduced. This paper studies the impact of these changes “from AODV to LOADng”, and observes that LOADng unites simplification, flexibility and performance improvements.}, keywords = {Constrained Networks, LLN, LOADng, MESH, Sensor Networks}, pubstate = {published}, tppubtype = {inproceedings} } The Ad hoc On-demand Distance-Vector routing protocol (AODV) was published in 2003 by the IETF, as ex- perimental RFC 3561. This routing protocol was one of four routing protocols, developed by the IETF for use in mobile ad hoc networks (MANETs) – with the other being DSR, TBRPF and OLSR. As operational experiences with these protocols accumulated, the IETF set forth on standardization of OLSRv2, a successor to OLSR, and DYMO – with DYMO being the intended successor to DSR and AODV. Alas, while there was traction for and standardization of OLSRv2, interest in, development, standardization, and use of DYMO in MANETs slowly withered. AODV did, however, attract interest for routing in Low-power Lossy Networks (LLNs) due to its limited state requirements. Since 2005, several proposals for simplifying and adapting AODV specifically for LLNs emerged, in 2011 and 2012 with the use of one such adaptation of AODV in the G3-PLC standard for power line communications in smart grids, and with efforts within the IETF emerging towards a single LOADng specification, as next version of AODV. This paper presents this development – from AODV, as specified in RFC3561 – to LOADng. While the basic operation remains unchanged, LOADng presents simplifications, and additional features and flexibilities are introduced. This paper studies the impact of these changes “from AODV to LOADng”, and observes that LOADng unites simplification, flexibility and performance improvements. |
2011 |
Yi, Jiazi; Clausen, Thomas; Herberg, Ulrich Vulnerability Analysis of the SMF Protocol for Mobile Ad Hoc Networks Inproceedings IEEE CPSCom 2011, 2011, (http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=6142260). Abstract | Links | BibTeX | Tags: Ad-Hoc, MANET, MESH, Security, SMF, SMF Security @inproceedings{Yi2011c, title = {Vulnerability Analysis of the SMF Protocol for Mobile Ad Hoc Networks}, author = {Jiazi Yi and Thomas Clausen and Ulrich Herberg}, url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2011-CPScom-Vulnerability-Analysis-of-the-Simple-Multicast-Forwarding-SMF-Protocol-for-Mobile-Ad-Hoc-Networks.pdf}, doi = {10.1109/iThings/CPSCom.2011.63}, year = {2011}, date = {2011-10-01}, publisher = {IEEE CPSCom 2011}, abstract = {If deployments of Mobile Ad Hoc Networks (MANETs) are to become common outside of purely experimental settings, protocols operating such MANETs must be able to preserve network integrity, even when faced with careless or malicious participants. A first step towards protecting a MANET is to analyze the vulnerabilities of the routing protocol(s), managing the connectivity. Understanding how these routing protocols can be exploited by those with ill intent, countermeasures can be developed, readying MANETs for wider deployment and use. One routing protocol for MANETs, developed by the Internet Engineering Task Force (IETF) as a multicast routing protocol for efficient data dissemination, is denoted "Simplified Multicast Forwarding'' (SMF). This protocol is analyzed, and its vulnerabilities described, in this paper. SMF consists of two independent components: (i) duplicate packet detection and (ii) relay set selection, each of which presents its own set of vulnerabilities that an attacker may exploit to compromise network integrity. This paper explores vulnerabilities in each of these, with the aim of identifying attack vectors and thus enabling development of countermeasures.}, note = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=6142260}, keywords = {Ad-Hoc, MANET, MESH, Security, SMF, SMF Security}, pubstate = {published}, tppubtype = {inproceedings} } If deployments of Mobile Ad Hoc Networks (MANETs) are to become common outside of purely experimental settings, protocols operating such MANETs must be able to preserve network integrity, even when faced with careless or malicious participants. A first step towards protecting a MANET is to analyze the vulnerabilities of the routing protocol(s), managing the connectivity. Understanding how these routing protocols can be exploited by those with ill intent, countermeasures can be developed, readying MANETs for wider deployment and use. One routing protocol for MANETs, developed by the Internet Engineering Task Force (IETF) as a multicast routing protocol for efficient data dissemination, is denoted "Simplified Multicast Forwarding'' (SMF). This protocol is analyzed, and its vulnerabilities described, in this paper. SMF consists of two independent components: (i) duplicate packet detection and (ii) relay set selection, each of which presents its own set of vulnerabilities that an attacker may exploit to compromise network integrity. This paper explores vulnerabilities in each of these, with the aim of identifying attack vectors and thus enabling development of countermeasures. |
