Thomas Heide Clausen
November 28, 2016
Introduction
The Lightweight On-demand Ad hoc Distance-vector Routing Protocol – Next Generation (LOADng) is a routing protocol, derived from AODV and extended for use in Mobile Ad hoc NETworks (MANETs) and Low-power and Lossy Networks (LLNs).
The LOADng control messages are carried by way of the Generalized MANET Packet/Message Format (RFC5444). Using the generalized message format, control messages can include TLV (Type-Length-Value) elements, permitting protocol extensions to be easily developed. LOADng supports routing using arbitrary additive metrics, which can be specified as extensions to this protocol.
LOADng has been ratified by ITU-T recommendation “G9903: Narrowband orthogonal frequency division multiplexing power line communication transceivers for G3-PLC networks” and has been deployed in G3-PLC Smart Grid.
Basic Route Discovery – Route Requests & Route Replies
As a reactive protocol, the basic operations of LOADng include:
- generation of Route Requests (RREQs) by a LOADng Router (originator) for discovering a route to a destination,
- forwarding of such RREQs until they reach the destination LOADng Router,
- generation of Route Replies (RREPs) upon receipt of an RREQ by the indicated destination, and
- unicast hop-by-hop forwarding of these RREPs towards the originator.
Figure 1 gives an example of RREQ message flooding. Router S initiates a route discovery to Router D. The RREQ message generated by Router S is retransmitted by other routers and flooded in the network until it reaches the destination router D. All the intermediate routers will set up a “reverse route” to Router S.
Please note that LOADng prohibits the intermediate route reply, i.e., even if the intermediate router has a route to the destination, it MUST NOT reply to the RREQ message, but simply forward the RREQ message.

Figure 1: LOADng Route Request Flooding and Route Installation
Figure 2 shows how unicast RREP message forwarding works. When the RREQ message reaches the destination router D, D will generate an RREP message. The RREP is unicast to the route discovery originator S following the reverse route established during the RREQ flooding. All the routers receiving the RREP message will establish a “forward route” to Router D.

Figure 2: LOADng Route Reply Unicast Forwarding and Route Installation
Route Maintenance
If a route is detected to be broken, e.g. if forwarding of a data packet to the recorded next hop on the route towards the intended destination is detected to fail, a Route Error (RERR) message is returned to the originator of that data packet to inform the originator about the route breakage.
Protocol Extensions
LOADng specifies a slim core that supports basic point-to-point route establishment that is suitable for common scenarios. To improve the protocol performance in special scenarios, such as data collection or existence of extremely unreliable links, different extensions are developed.
Smart Route Request
In some network types, such as sensor networks, it is common to have sensor-to-root (multipoint-to-point — or MP2P) traffic. While eliminating intermediate RREPs can reduce the size of control message and simplify the protocol process, the side effect of blindly flooding RREQ cannot be ignored in this kind of scenarios.
Smart Route Request is thus proposed to replace intermediate route reply while retaining the loop-freedom nature and security mechanism of LOADng. When Smart Route Request is used, if an intermediate LOADng router has already a routing entry to the destination, it will retransmit the RREQ message to the destination by unicast, instead of multicast. More details about the Smart Route Request can be found at:
Expanding Ring Search
The expanding ring search aims at reducing the flooding area of RREQ messages so as to reduce the message overhead. A router will at first send an RREQ with a reduced TTL (Time-To-Live) — causing the RREQ to not be flooded through the entire network, but only up to a limited distance. If the destination sought receives the RREQ, or an intermediate router has a path to the sought destination, an RREP (possibly intermediate/gratuitous) is generated and a network-wide flooding is avoided. If no RREP is received by the originator in expected delay, another RREQ message is, after a brief delay, generated with increased TTL to eventually cover the entire network. More details about the expanding ring search can be found at:
Collection Tree Protocol
The point-to-point traffic pattern supported by LOADng matches the basic traffic model of the Internet. However, in many deployments of LLNs, another important traffic pattern, called sensor-to-root, or multipoint-to-point, exists. In such traffic scenarios, there is one or more devices that plays the role as “root” — data sink for all traffic — and where all the other devices in the network communicate with the root. If paths from all the other devices to the root are required, it is more efficient to build a “collection tree” (i.e., a directed graph in which all edges are oriented toward and terminate at one root router) and to discover and maintain the set of point-to-point routes from all other routers to that “root”. The collection tree extension aims at building bi-directional routes between the root router and all other routers. More details about the collection tree extension can be found at:
Depth First Forwarding
Depth-First Forwarding in Unreliable Networks (DFF) is an experimental data forwarding standard by the IETF, which proposes a mechanism for rapid and localized recovery in case of link failure. Colloquially speaking, if a device fails in its attempt to forward a packet to its intended next-hop, then DFF suggests a heuristics for “trying another of that devices’ neighbors”, while keeping track of (and preventing) packet loops.
LOADng is extended to support DFF by adding neighbor discovery mechanisms using HELLO messages. The simulation results show that the DFF could effectively increase the packet delivery ratio at the cost of increasing end-to-end delay and longer path length. More details can be found at:
Interoperability Tests
Five interoperability test events have been organised to improve the protocol specification and verify that interoperable implementations can be developed based on the document. A detailed interop report can be found at Interoperability Report for the Lightweight On-demand Ad hoc Distance-vector Routing Protocol – Next Generation (LOADng).
- Interop 01: The first LOADng interoperability test event was held at Hitachi YRL in Yokohama, Japan, from October 17th to October 19th, 2011. The interoperability tests were conducted according to the specification in LOADng-00. Ecole Polytechnique, Hitachi YRL and EDF R&D participated in the tests. Three implementations (1 from Ecole Polytechnique and 2 from Hitachi YRL) were tested.
- Interop 02: The second LOADng interoperability test event was held at Fujitsu Laboratories of America (FLA), San Jose, USA, on April 13th, 2012. The interoperability tests were conducted according to the specification in LOADng-03. Ecole Polytechnique and Fujitsu Lab of America (FLA) participated in the tests. Two implementations (1 from Ecole Polytechnique and 1 from Fujitsu FLA) were tested.
- Interop 03: The third LOADng interoperability test event was performed at the Los Angeles Airport Hilton, USA, on June 6th, 2012. The interoperability tests were conducted according to the specification in LOADng-04. Ecole Polytechnique and Fujitsu Lab of America (FLA) participated in the tests. Two implementations: 1 from Ecole Polytechnique and 1 from Fujitsu FLA were tested.
- Interop 04: The fourth LOADng interoperability test event was held at Hyatt Hotel, Vancouver, August 2nd, 2012. The interoperability tests were conducted according to the specification in LOADng-05. Ecole Polytechnique and Fujitsu Lab of America (FLA) participated in the tests. Two implementations (1 from Ecole Polytechnique and 1 from Fujitsu FLA) were tested.
- Interop 05: The fifth LOADng interoperability test even was performed at Sagemcom Rueil-Malmaison, France from August 2nd to August 5th, 2016. Ecole Polytechnique, Sagemcom and Nexans participated in the tests. Two implementations (1 from Sagemcom and 1 from Nexans) were tested. The LOADng protocol tested was based on specification “G3-PLC over Medium Voltage Lines: Implementation Guidelines“.
A World-Wide Community
- Initiated by an industrial need, satisfied by us, used world-wode
- Links to known implementations
- Link to ITU standard
Related Publications
Morales, Jesús A. Cumana; Coupechoux, Marceau; Cordero, Juan Antonio
Metasurface for Enhanced Millimeter-Wave Communications under Imperfect Beam Alignment Proceedings Article Forthcoming
In: Proc. IEEE International Mediterranean Conference on Communications and Networking (MeditCom'2023), IEEE, Forthcoming.
@inproceedings{nokey,
title = {Metasurface for Enhanced Millimeter-Wave Communications under Imperfect Beam Alignment},
author = {Jesús A. Cumana Morales and Marceau Coupechoux and Juan Antonio Cordero},
year = {2023},
date = {2023-09-04},
urldate = {2023-09-04},
booktitle = {Proc. IEEE International Mediterranean Conference on Communications and Networking (MeditCom'2023)},
publisher = {IEEE},
abstract = {In this work, we investigate the impact of beam misalignment in the performance of a wireless system employing a metasurface to improve coverage in a non-line-of-sight (NLOS) scenario. The metasurface is modeled by an array of small radiating elements each of them terminated with a complex load. An equivalent Array Factor is defined, which allows visualizing the beamsteering properties of the metasurface in far-field conditions. Angular misalignment is modeled using a truncated Gaussian distribution and an expression to evaluate signal-to-noise ratio (SNR) in the presence of misalignment is derived. Numerical results show an SNR degradation close to 8 dB for 5° error magnitude and up to 14 dB if high-gain unit cells are used. Three mechanisms are explored, which can be used to reduce SNR degradation: increasing Metasurface dimensions allows recovering SNR by 7.4 dB, low unit cell gain allows improving SNR by close to 10.5 dB when compared to a high-gain cell and base station beamwidth decrease from 25.6° to 12.7° allows recovering SNR by 4 dB thanks to the higher BS beam gain. },
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In this work, we investigate the impact of beam misalignment in the performance of a wireless system employing a metasurface to improve coverage in a non-line-of-sight (NLOS) scenario. The metasurface is modeled by an array of small radiating elements each of them terminated with a complex load. An equivalent Array Factor is defined, which allows visualizing the beamsteering properties of the metasurface in far-field conditions. Angular misalignment is modeled using a truncated Gaussian distribution and an expression to evaluate signal-to-noise ratio (SNR) in the presence of misalignment is derived. Numerical results show an SNR degradation close to 8 dB for 5° error magnitude and up to 14 dB if high-gain unit cells are used. Three mechanisms are explored, which can be used to reduce SNR degradation: increasing Metasurface dimensions allows recovering SNR by 7.4 dB, low unit cell gain allows improving SNR by close to 10.5 dB when compared to a high-gain cell and base station beamwidth decrease from 25.6° to 12.7° allows recovering SNR by 4 dB thanks to the higher BS beam gain.
Cordero, Juan Antonio; Lou, Wei
Modeling Dynamic Resource Allocation in the Edge Proceedings Article
In: Proceedings of the 8th IFIP/IEEE International Conference on Performance Evaluation and Modeling in Wired and Wireless Networks (PEMWN'2019).
, IEEE, 2019.
@inproceedings{Cordero2019,
title = { Modeling Dynamic Resource Allocation in the Edge},
author = {Juan Antonio Cordero and Wei Lou},
year = {2019},
date = {2019-11-26},
urldate = {2019-11-26},
booktitle = {Proceedings of the 8th IFIP/IEEE International Conference on Performance Evaluation and Modeling in Wired and Wireless Networks (PEMWN'2019).
},
publisher = {IEEE},
abstract = {Edge computing technologies and integrated archi- tectures have been deployed to accommodate Internet traffic growth. These architectures include facilities (cloudlets, micro DCs) to cache and serve contents close to consumers. Resulting systems adapt to observed request/consumption patterns by allowing cloudlet coordination for content caching/dissemination. This paper presents a novel analytical model of transient dy- namics of the cloudlets set. The model is used to study system convergence, stability and delivered content locality. Results from this model are validated via simulations.},
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tppubtype = {inproceedings}
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Edge computing technologies and integrated archi- tectures have been deployed to accommodate Internet traffic growth. These architectures include facilities (cloudlets, micro DCs) to cache and serve contents close to consumers. Resulting systems adapt to observed request/consumption patterns by allowing cloudlet coordination for content caching/dissemination. This paper presents a novel analytical model of transient dy- namics of the cloudlets set. The model is used to study system convergence, stability and delivered content locality. Results from this model are validated via simulations.
Desmouceaux, Yoann; Clausen, Thomas; Cordero, Juan Antonio; Townsley, W. Mark
Reliable Multicast with B.I.E.R. Journal Article
In: IEEE/KICS Journal of Communications and Networks (JCN), vol. 20, no. 2, pp. 182-197, 2018.
@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.},
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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.
Cordero, Juan Antonio
Multi-Path TCP Performance Evaluation in Dual-Homed (Wired/Wireless) Devices Journal Article
In: Journal of Network and Computer Applications , vol. 70, pp. 131-139, 2016, ISSN: 1084-8045.
@article{Cordero2016,
title = {Multi-Path TCP Performance Evaluation in Dual-Homed (Wired/Wireless) Devices},
author = {Juan Antonio Cordero},
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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.},
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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.
Yi, Jiazi; Clausen, Thomas; Igarashi, Yuichi
Evaluation of Routing Protocol for Low Power and Lossy Networks: LOADng and RPL Proceedings Article
In: 2013 IEEE Conference on Wireless Sensors, 2013.
@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.},
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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 Proceedings Article
In: IEEE 15th International Conference on Communication Technology, 2013.
@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 = {},
pubstate = {published},
tppubtype = {inproceedings}
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“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.
Cordero, Juan Antonio; Philipp, Matias; Baccelli, Emmanuel
Routing across Wired and Wireless Mesh Networks: Experimental Compound Internetworking with OSPF Proceedings Article
In: Proceedings of the 8th IEEE International Wireless Communications and Mobile Computing Conference (WCMC 2012), 2012.
@inproceedings{Cordero2012b,
title = {Routing across Wired and Wireless Mesh Networks: Experimental Compound Internetworking with OSPF},
author = {Juan Antonio Cordero and Matias Philipp and Emmanuel Baccelli},
url = {https://www.researchgate.net/publication/236883800_Routing_Across_Wired_and_Wireless_Mesh_Networks_Experimental_Compound_Internetworking_with_OSPF},
doi = {10.1109/IWCMC.2012.6314296},
year = {2012},
date = {2012-08-01},
publisher = {Proceedings of the 8th IEEE International Wireless Communications and Mobile Computing Conference (WCMC 2012)},
abstract = {As wireless mesh networks are deployed, a new concept emerges: compound internetworks, i.e., internetworks that contain both wired networks and wireless mesh networks. Routing is one of the key challenges that arises in compound internetworks: indeed, while specific routing protocols are typically used for wired networks on one hand, and for wireless mesh networks on the other hand, it has been observed that operating a single routing protocol to manage a compound internetwork as a whole brings several advantages. In this realm, the IETF has thus standardized protocol extensions to Open Shortest Path First (OSPF, the routing protocol used by more than 50 % of the wired routers in today's Internet), enabling OSPF to operate simultaneously on wired networks, and on wireless mesh or moderately mobile ad hoc networks (MANETs). This paper evaluates the performance of OSPF coupled with such a protocol extension for MANETs on an experimental compound internetwork testbed. This paper reports on experiments carried out with OSPF operating simul-taneously over Ethernet and 802.11b. Despite the limitations of the testbed, these experiments provide both a proof-of-concept and complementary results compared to prior work in the domain, which was mostly based on simulations, and focused on wireless ad hoc network scenarios only.},
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As wireless mesh networks are deployed, a new concept emerges: compound internetworks, i.e., internetworks that contain both wired networks and wireless mesh networks. Routing is one of the key challenges that arises in compound internetworks: indeed, while specific routing protocols are typically used for wired networks on one hand, and for wireless mesh networks on the other hand, it has been observed that operating a single routing protocol to manage a compound internetwork as a whole brings several advantages. In this realm, the IETF has thus standardized protocol extensions to Open Shortest Path First (OSPF, the routing protocol used by more than 50 % of the wired routers in today's Internet), enabling OSPF to operate simultaneously on wired networks, and on wireless mesh or moderately mobile ad hoc networks (MANETs). This paper evaluates the performance of OSPF coupled with such a protocol extension for MANETs on an experimental compound internetwork testbed. This paper reports on experiments carried out with OSPF operating simul-taneously over Ethernet and 802.11b. Despite the limitations of the testbed, these experiments provide both a proof-of-concept and complementary results compared to prior work in the domain, which was mostly based on simulations, and focused on wireless ad hoc network scenarios only.
Herberg, Ulrich; Clausen, Thomas
Study of Multipoint-to-Point and Broadcast Traffic Performance in the 'IPv6 Routing Protocol for Low Power and Lossy Networks' (RPL) Journal Article
In: Journal of Ambient Intelligence and Humanized Computing, Springer, ISSN 1868-5137, Volume 2, Number 4, 2011, (http://link.springer.com/article/10.1007/s12652-011-0046-2).
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title = {Study of Multipoint-to-Point and Broadcast Traffic Performance in the 'IPv6 Routing Protocol for Low Power and Lossy Networks' (RPL)},
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journal = {Journal of Ambient Intelligence and Humanized Computing, Springer, ISSN 1868-5137, Volume 2, Number 4},
abstract = {Recent trends in Wireless Sensor Networks (WSNs) have suggested converging to such being IPv6-based. To this effect, the Internet Engineering Task Force has chartered a Working Group to develop a routing protocol specification, enabling IPv6-based multi-hop Wireless Sensor Networks. This routing protocol, denoted “IPv6 Routing Protocol for Low Power and Lossy Networks” (RPL), has been under development for approximately a year, and this paper takes a critical look at the state of advancement hereof: it provides a brief algorithmic description of the protocol, and discusses areas where—in the authors view—further efforts are required in order for the protocol to become a viable candidate for general use in WSNs. Among these areas is the lack of a proper broadcast mechanism. This paper suggests several such broadcast mechanisms, all aiming at (1) exploiting the existing routing state of RPL, while (2) requiring no additional state maintenance, and studies the performance of RPL and of these suggested mechanisms.},
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Recent trends in Wireless Sensor Networks (WSNs) have suggested converging to such being IPv6-based. To this effect, the Internet Engineering Task Force has chartered a Working Group to develop a routing protocol specification, enabling IPv6-based multi-hop Wireless Sensor Networks. This routing protocol, denoted “IPv6 Routing Protocol for Low Power and Lossy Networks” (RPL), has been under development for approximately a year, and this paper takes a critical look at the state of advancement hereof: it provides a brief algorithmic description of the protocol, and discusses areas where—in the authors view—further efforts are required in order for the protocol to become a viable candidate for general use in WSNs. Among these areas is the lack of a proper broadcast mechanism. This paper suggests several such broadcast mechanisms, all aiming at (1) exploiting the existing routing state of RPL, while (2) requiring no additional state maintenance, and studies the performance of RPL and of these suggested mechanisms.
Herberg, Ulrich; Clausen, Thomas
A Comparative Performance Study of the Routing Protocols LOAD and RPL with Bi-Directional Traffic in Low-power and Lossy Networks (LLN) Proceedings Article
In: Proceedings of the Eighth ACM International Symposium on Performance Evaluation of Wireless Ad Hoc, Sensor, and Ubiquitous Networks (PE-WASUN), 2011.
@inproceedings{Clausen2011a,
title = {A Comparative Performance Study of the Routing Protocols LOAD and RPL with Bi-Directional Traffic in Low-power and Lossy Networks (LLN)},
author = {Ulrich Herberg and Thomas Clausen},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2011-PE-WASUN-A-Comparative-Performance-Study-of-the-Routing-Protocols-LOAD-and-RPL-with-Bi-Directional-Traffic-in-Low-power-and-Lossy-Networks-LLN.pdf},
doi = {10.1145/2069063.2069076},
year = {2011},
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publisher = {Proceedings of the Eighth ACM International Symposium on Performance Evaluation of Wireless Ad Hoc, Sensor, and Ubiquitous Networks (PE-WASUN)},
abstract = {Routing protocols for sensor networks are often designed with explicit assumptions, serving to simplify design and re-duce the necessary energy, processing and communications requirements. Different protocols make different assump-tions – and this paper considers those made by the designers of RPL – an IPv6 routing protocol for such networks, de-veloped within the IETF. Specific attention is given to the predominance of bi-directional traffic flows in a large class of sensor networks, and this paper therefore studies the per-formance of RPL for such flows. As a point of comparison, a different protocol, called LOAD, is also studied. LOAD is derived from AODV and supports more general kinds of traffic flows. The results of this investigation reveal that for scenarios where bi-directional traffic flows are predomi-nant, LOAD provides similar data delivery ratios as RPL, while incurring less overhead and being simultaneously less constrained in the types of topologies supported.},
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tppubtype = {inproceedings}
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Routing protocols for sensor networks are often designed with explicit assumptions, serving to simplify design and re-duce the necessary energy, processing and communications requirements. Different protocols make different assump-tions – and this paper considers those made by the designers of RPL – an IPv6 routing protocol for such networks, de-veloped within the IETF. Specific attention is given to the predominance of bi-directional traffic flows in a large class of sensor networks, and this paper therefore studies the per-formance of RPL for such flows. As a point of comparison, a different protocol, called LOAD, is also studied. LOAD is derived from AODV and supports more general kinds of traffic flows. The results of this investigation reveal that for scenarios where bi-directional traffic flows are predomi-nant, LOAD provides similar data delivery ratios as RPL, while incurring less overhead and being simultaneously less constrained in the types of topologies supported.
Cordero, Juan Antonio
Link-State Routing Optimization for Compound Autonomous Systems in the Internet PhD Thesis
École polytechnique, 2011.
@phdthesis{Cordero2011b,
title = {Link-State Routing Optimization for Compound Autonomous Systems in the Internet},
author = {Juan Antonio Cordero},
url = {https://www.researchgate.net/publication/262343881_Link-State_Routing_Optimization_for_Compound_Autonomous_Systems_in_the_Internet},
year = {2011},
date = {2011-09-15},
address = {Palaiseau, France},
school = {École polytechnique},
abstract = {This manuscript addresses the coexistence of planned and spontaneous interconnected networks in the Internet core. In this realm, the focus is on routing within a specific type of Autonomous System (AS) called compound AS, which contains both wireless ad hoc networks and wired fixed networks. The approach studied in this manuscript is to enhance existing Interior Gateway Protocols (IGPs), typically based on the link-state algorithm, in order to enable them to operate both in ad hoc networks and in wired networks. The manuscript thus analyzes the use of link-state routing in ad hoc networks. Based on this analysis, different techniques are proposed and theoretically evaluated, aiming at optimizing the performance of link state routing in a compound AS. The manuscript then investigates the impact of these techniques when applied to OSPF, one of the main IGPs used in the Internet. The performance of OSPF extensions on MANETs using the studied techniques are compared via simulations. Finally, OSPF operation over compound internetworks is evaluated via experiments on a testbed.},
keywords = {},
pubstate = {published},
tppubtype = {phdthesis}
}
This manuscript addresses the coexistence of planned and spontaneous interconnected networks in the Internet core. In this realm, the focus is on routing within a specific type of Autonomous System (AS) called compound AS, which contains both wireless ad hoc networks and wired fixed networks. The approach studied in this manuscript is to enhance existing Interior Gateway Protocols (IGPs), typically based on the link-state algorithm, in order to enable them to operate both in ad hoc networks and in wired networks. The manuscript thus analyzes the use of link-state routing in ad hoc networks. Based on this analysis, different techniques are proposed and theoretically evaluated, aiming at optimizing the performance of link state routing in a compound AS. The manuscript then investigates the impact of these techniques when applied to OSPF, one of the main IGPs used in the Internet. The performance of OSPF extensions on MANETs using the studied techniques are compared via simulations. Finally, OSPF operation over compound internetworks is evaluated via experiments on a testbed.
Clausen, Thomas; Herberg, Ulrich
Comparative Study of RPL-Enabled Optimized Broadcast in Wireless Sensor Networks Proceedings Article
In: Proceedings of the 6th International Conference on Intelligent Sensors, Sensor Networks and Information Processing (ISSNIP), 2010.
@inproceedings{Clausen2010e,
title = {Comparative Study of RPL-Enabled Optimized Broadcast in Wireless Sensor Networks},
author = {Thomas Clausen and Ulrich Herberg},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2010-ISSNIP-Comparative-Study-of-RPL-Enabled-Optimized-Broadcast-in-Wireless-Sensor-Networks.pdf},
doi = {10.1109/ISSNIP.2010.5706795},
year = {2010},
date = {2010-12-01},
publisher = {Proceedings of the 6th International Conference on Intelligent Sensors, Sensor Networks and Information Processing (ISSNIP)},
abstract = {Recent trends have suggested convergence to Wire-less Sensor Networks (WSNs) becoming IPv6-based. To this effect, the Internet Engineering Task Force has chartered a Work-ing Group to develop a routing protocol specification, enabling IPv6-based multi-hop Wireless Sensor Networks. The current effort of this working group is development of a uni-cast routing protocol denoted RPL. RPL constructs a “DAG-like” logical structure with a single root, at which the majority of the traffic flows terminate, and assumes restrictions on network dynamics and traffic generality, in order to satisfy strict constraints on router state and processing. This paper investigates the possibility for providing (effi-cient) network-wide broadcast mechanisms in WSNs, using the logical structure already provided by RPL. The aim hereof is to not impose any additional state requirements on WSN routers already running RPL. This paper presents two such broadcast mechanisms for RPL routed WSNs, and evaluates their performances. As part of this evaluation, the paper compares with MPR Flooding – an established efficient flooding optimization, widely used in MANETs.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
Recent trends have suggested convergence to Wire-less Sensor Networks (WSNs) becoming IPv6-based. To this effect, the Internet Engineering Task Force has chartered a Work-ing Group to develop a routing protocol specification, enabling IPv6-based multi-hop Wireless Sensor Networks. The current effort of this working group is development of a uni-cast routing protocol denoted RPL. RPL constructs a “DAG-like” logical structure with a single root, at which the majority of the traffic flows terminate, and assumes restrictions on network dynamics and traffic generality, in order to satisfy strict constraints on router state and processing. This paper investigates the possibility for providing (effi-cient) network-wide broadcast mechanisms in WSNs, using the logical structure already provided by RPL. The aim hereof is to not impose any additional state requirements on WSN routers already running RPL. This paper presents two such broadcast mechanisms for RPL routed WSNs, and evaluates their performances. As part of this evaluation, the paper compares with MPR Flooding – an established efficient flooding optimization, widely used in MANETs.
Cordero, Juan Antonio
Adjacency Persistency in OSPF MANET Proceedings Article
In: Proceedings of the 4th IET China-Ireland International Conference on Information and Communication Technologies (CIICT’2010)., 2010.
@inproceedings{Cordero2010,
title = {Adjacency Persistency in OSPF MANET},
author = {Juan Antonio Cordero},
url = {https://www.researchgate.net/publication/46388530_Adjacency_Persistency_in_OSPF_MANET},
year = {2010},
date = {2010-10-01},
publisher = {Proceedings of the 4th IET China-Ireland International Conference on Information and Communication Technologies (CIICT’2010).},
abstract = {Link-state routing remains as one of the most challenging issues in ad hoc networking, due to the special conditions and requirements that hold in such networks, which cannot be handled by classical routing protocols. In the last decade, several efforts have been deployed either to design new routing solutions adapted to ad hoc conditions, either to extend existing solutions for wired networks to the domain of wireless mobile scenarios. This paper elaborates on the latter alternative, focusing on the standard OSPF MANET extension RFC 5449. It analyzes the impact and interest of the persistency principle to the main OSPF MANET operations, in particular the adjacency synchronization and the other operations that relate to it (flooding and route construction). The presented results show that such persistent approach is appropriate for managing adjacencies in the context of RFC 5449, and significant improvements might be achieved by extending the persistent principle into the topology selection mechanism.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
Link-state routing remains as one of the most challenging issues in ad hoc networking, due to the special conditions and requirements that hold in such networks, which cannot be handled by classical routing protocols. In the last decade, several efforts have been deployed either to design new routing solutions adapted to ad hoc conditions, either to extend existing solutions for wired networks to the domain of wireless mobile scenarios. This paper elaborates on the latter alternative, focusing on the standard OSPF MANET extension RFC 5449. It analyzes the impact and interest of the persistency principle to the main OSPF MANET operations, in particular the adjacency synchronization and the other operations that relate to it (flooding and route construction). The presented results show that such persistent approach is appropriate for managing adjacencies in the context of RFC 5449, and significant improvements might be achieved by extending the persistent principle into the topology selection mechanism.
Clausen, Thomas; Viennot, Laurent; Olesen, Tue; Larsen, Nikolai
Investigating data broadcast performance in mobile ad-hoc networks Proceedings Article
In: Wireless Personal Multimedia Communications, 2002. The 5th International Symposium on, pp. 786-790 vol.2, 2002, ISSN: 1347-6890.
@inproceedings{Clausen2002a,
title = {Investigating data broadcast performance in mobile ad-hoc networks},
author = {Thomas Clausen and Laurent Viennot and Tue Olesen and Nikolai Larsen},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2002-WPMC-Investigating-data-broadcast-performance-in-mobile-ad-hoc-networks.pdf},
doi = {10.1109/WPMC.2002.1088283},
issn = {1347-6890},
year = {2002},
date = {2002-10-01},
booktitle = {Wireless Personal Multimedia Communications, 2002. The 5th International Symposium on},
volume = {2},
pages = {786-790 vol.2},
abstract = {We investigate broadcasting in mobile ad-hoc networks (MANETs). We define broadcasting as being the process of delivering one packet, originated at one node, to (ideally) all other nodes in the MANET. We present specific problems related to broadcasting in MANETs, as well as four broadcast protocols aimed at providing MANET-wide broadcast. Further, three protocol-independent modifications are presented. One aimed at ensuring that a broadcast packet traverses at least the "shortest path" to its destinations, and two aimed at increasing the fraction of nodes which receive a broadcast packet. Through simulation studies, we evaluate the performance characteristics of the broadcast protocols and generic modifications under different conditions.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We investigate broadcasting in mobile ad-hoc networks (MANETs). We define broadcasting as being the process of delivering one packet, originated at one node, to (ideally) all other nodes in the MANET. We present specific problems related to broadcasting in MANETs, as well as four broadcast protocols aimed at providing MANET-wide broadcast. Further, three protocol-independent modifications are presented. One aimed at ensuring that a broadcast packet traverses at least the "shortest path" to its destinations, and two aimed at increasing the fraction of nodes which receive a broadcast packet. Through simulation studies, we evaluate the performance characteristics of the broadcast protocols and generic modifications under different conditions.
Clausen, Thomas; Jacquet, Philippe; Viennot, Laurent
Investigating the impact of partial topology in proactive MANET routing protocols Proceedings Article
In: Wireless Personal Multimedia Communications, 2002. The 5th International Symposium on, pp. 1374-1378 vol.3, 2002, ISSN: 1347-6890.
@inproceedings{Clausen2002,
title = {Investigating the impact of partial topology in proactive MANET routing protocols},
author = {Thomas Clausen and Philippe Jacquet and Laurent Viennot},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2002-WPMC-Investigating-the-impact-of-partial-topology-in-proactive-MANET-routing-protocols.pdf},
doi = {10.1109/WPMC.2002.1088405},
issn = {1347-6890},
year = {2002},
date = {2002-10-01},
booktitle = {Wireless Personal Multimedia Communications, 2002. The 5th International Symposium on},
volume = {3},
pages = {1374-1378 vol.3},
abstract = {We study the impact of using partial versus full topology in the OLSR (optimized link state routing) protocol for MANETs (mobile ad hoc networks). The core of OLSR is the notion of multi-point relays (MPRs), serving the purpose of reducing the amount of link-state information flooded to nodes in the network, as well as reducing the redundancy in the flooding process. The OLSR protocol specification contains a tunable parameter, MPR coverage, which adjusts the degree of redundancy in both the advertised link-state information, and the links over which the link-state information is advertised. We investigate the impact of assigning various values to this parameter. We further investigate two options for advertising additional link-state information: the "MPR full link-state" option implies that whenever a node is selected to declare any link-state information, it declares all its local link state information; the "full link-state" option states, that all nodes must declare all their local link-state information. Through simulations, we investigate the performance characteristics of OLSR with and without these options.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We study the impact of using partial versus full topology in the OLSR (optimized link state routing) protocol for MANETs (mobile ad hoc networks). The core of OLSR is the notion of multi-point relays (MPRs), serving the purpose of reducing the amount of link-state information flooded to nodes in the network, as well as reducing the redundancy in the flooding process. The OLSR protocol specification contains a tunable parameter, MPR coverage, which adjusts the degree of redundancy in both the advertised link-state information, and the links over which the link-state information is advertised. We investigate the impact of assigning various values to this parameter. We further investigate two options for advertising additional link-state information: the "MPR full link-state" option implies that whenever a node is selected to declare any link-state information, it declares all its local link state information; the "full link-state" option states, that all nodes must declare all their local link-state information. Through simulations, we investigate the performance characteristics of OLSR with and without these options.
Clausen, Thomas; Jacquet, Philippe; Viennot, Laurent
Comparative Study of Routing Protocols for Mobile Ad-hoc NETworks Proceedings Article
In: Proceedings of the IFIP MedHocNet, September 2002, Sardinia, Italy, 2002.
@inproceedings{Clausen2002c,
title = {Comparative Study of Routing Protocols for Mobile Ad-hoc NETworks},
author = {Thomas Clausen and Philippe Jacquet and Laurent Viennot},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2002-MedHocNets-Comparative-Study-of-Routing-Protocols-for-Mobile-Ad-hoc-NETwork.pdf},
year = {2002},
date = {2002-09-01},
booktitle = {Proceedings of the IFIP MedHocNet, September 2002, Sardinia, Italy},
abstract = {In this paper, we describe the Optimized Link State Routing Protocol (OLSR) [19],[20], a proactive routing protocol for Mobile Ad-hoc NETworks (MANETs). We eval- uate its performance through exhaustive simulations using the Network Simulator 2 (ns2) [1], and compare with other ad-hoc protocols, specifically the Ad-hoc On-Demand Dis- tance Vector (AODV) [4] routing protocol and the Dynamic Source Routing (DSR) [5] protocol. We study the protocols under varying conditions (node mobility, network density) and with varying traffic (TCP, UDP, different number of connections/streams) to provide a qualitative assessment of the applicability of the protocols in different scenarios.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
In this paper, we describe the Optimized Link State Routing Protocol (OLSR) [19],[20], a proactive routing protocol for Mobile Ad-hoc NETworks (MANETs). We eval- uate its performance through exhaustive simulations using the Network Simulator 2 (ns2) [1], and compare with other ad-hoc protocols, specifically the Ad-hoc On-Demand Dis- tance Vector (AODV) [4] routing protocol and the Dynamic Source Routing (DSR) [5] protocol. We study the protocols under varying conditions (node mobility, network density) and with varying traffic (TCP, UDP, different number of connections/streams) to provide a qualitative assessment of the applicability of the protocols in different scenarios.
Viennot, Laurent; Jacquet, Philippe; Clausen, Thomas
Analyzing Control Traffic Overhead in Mobile Ad-hoc Network Protocols versus Mobility and Data Traffic Activity Proceedings Article
In: In Proceedings of the 1st IFIP Annual Mediterranean Ad Hoc Networking Workshop (MedHocNet’02, 2002.
@inproceedings{Viennot2002,
title = {Analyzing Control Traffic Overhead in Mobile Ad-hoc Network Protocols versus Mobility and Data Traffic Activity},
author = {Laurent Viennot and Philippe Jacquet and Thomas Clausen},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2002-MedHocNet-Analyzing-Control-Traffic-Overhead-versus-Mobility-and-Data-Traffic-Activity-in-Mobile-Ad-hoc-Network-Protocols.pdf},
year = {2002},
date = {2002-01-01},
booktitle = {In Proceedings of the 1st IFIP Annual Mediterranean Ad Hoc Networking Workshop (MedHocNet’02},
abstract = {This paper proposes a general, parameterized model for analyzing protocol control overheads in mobile ad-hoc networks. A probabilistic model for the network topology and the data traffic is proposed in order to estimate overhead due to control packets of routing protocols.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper proposes a general, parameterized model for analyzing protocol control overheads in mobile ad-hoc networks. A probabilistic model for the network topology and the data traffic is proposed in order to estimate overhead due to control packets of routing protocols.
Clausen, Thomas; Hansen, Gitte; Christensen, Lars; Behrmann, Gerd
The Optimized Link State Routing Protocol Evaluation through Experiments and Simulation Proceedings Article
In: IN PROCEEDING OF WIRELESS PERSONAL MULTIMEDIA COMMUNICATIONS, IEEE, 2001.
@inproceedings{Clausen2001,
title = {The Optimized Link State Routing Protocol Evaluation through Experiments and Simulation},
author = {Thomas Clausen and Gitte Hansen and Lars Christensen and Gerd Behrmann},
url = {http://www.thomasclausen.net/wp-content/uploads/2015/12/2001-WPMC-The-Optimized-Link-State-Routing-Protocol-Evaluation-through-Experiments-and-Simulation.pdf},
year = {2001},
date = {2001-01-01},
booktitle = {IN PROCEEDING OF WIRELESS PERSONAL MULTIMEDIA COMMUNICATIONS},
publisher = {IEEE},
abstract = {In this paper, we describe the Optimized Link State Routing Protocol (OLSR) [1] for Mobile Ad-hoc NETworks (MANETs) and the evaluation of this protocol through experiments and simulations. In particular, we emphasize the practical tests and intensive simulations, which have been used in guiding and evaluating the design of the protocol, and which have been a key to identifying both problems and solutions. OLSR is a proactive link-state routing protocol, employing periodic message exchange for updating topological information in each node in the network. I.e. topological information is flooded to all nodes in the network. Conceptually, OLSR contains three elements: Mechanisms for neighbor sensing based on periodic exchange of HELLO messages within a node’s neighborhood. Generic mechanisms for efficient flooding of control traffic into the network employing the concept of multipoint relays (MPRs) [5] for a significant reduction of duplicate retransmissions during the flooding process. And a specification of a set of control-messages providing each node with sufficient topological information to be able to compute an optimal route to each destination in the network using any shortest-path algorithm. Experimental work, running a test-network of laptops with IEEE 802.11 wireless cards, revealed interesting properties. While the protocol, as originally specified, works quite well, it was found, that enforcing “jitter” on the interval between the periodic exchange of control messages in OLSR and piggybacking said control messages into a single packet, significantly reduced the number of messages lost due to collisions. It was also observed, that under certain conditions a “naive” neighbor sensing mechanism was insufficient: a bad link between two nodes (e.g. when two nodes are on the edge of radio range) might on occasion transmit a HELLO message in both directions (hence enabling the link for routing), while not being able to sustain continuous traffic. This would result in “route-flapping” and temporary loss of connectivity. With the experimental results as basis, we have been deploying simulations to reveal the impact of the various algorithmic improvements, described above.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
In this paper, we describe the Optimized Link State Routing Protocol (OLSR) [1] for Mobile Ad-hoc NETworks (MANETs) and the evaluation of this protocol through experiments and simulations. In particular, we emphasize the practical tests and intensive simulations, which have been used in guiding and evaluating the design of the protocol, and which have been a key to identifying both problems and solutions. OLSR is a proactive link-state routing protocol, employing periodic message exchange for updating topological information in each node in the network. I.e. topological information is flooded to all nodes in the network. Conceptually, OLSR contains three elements: Mechanisms for neighbor sensing based on periodic exchange of HELLO messages within a node’s neighborhood. Generic mechanisms for efficient flooding of control traffic into the network employing the concept of multipoint relays (MPRs) [5] for a significant reduction of duplicate retransmissions during the flooding process. And a specification of a set of control-messages providing each node with sufficient topological information to be able to compute an optimal route to each destination in the network using any shortest-path algorithm. Experimental work, running a test-network of laptops with IEEE 802.11 wireless cards, revealed interesting properties. While the protocol, as originally specified, works quite well, it was found, that enforcing “jitter” on the interval between the periodic exchange of control messages in OLSR and piggybacking said control messages into a single packet, significantly reduced the number of messages lost due to collisions. It was also observed, that under certain conditions a “naive” neighbor sensing mechanism was insufficient: a bad link between two nodes (e.g. when two nodes are on the edge of radio range) might on occasion transmit a HELLO message in both directions (hence enabling the link for routing), while not being able to sustain continuous traffic. This would result in “route-flapping” and temporary loss of connectivity. With the experimental results as basis, we have been deploying simulations to reveal the impact of the various algorithmic improvements, described above.
Cordero, Juan Antonio; Lou, Wei
Modeling Dynamic Resource Allocation in the Edge Proceedings Article Forthcoming
In: Proceedings of the 8th IFIP/IEEE International Conference on Performance Evaluation and Modeling in Wired and Wireless Networks (PEMWN'2019).
, IEEE, Forthcoming.
@inproceedings{Cordero2019,
title = { Modeling Dynamic Resource Allocation in the Edge},
author = {Juan Antonio Cordero and Wei Lou},
booktitle = {Proceedings of the 8th IFIP/IEEE International Conference on Performance Evaluation and Modeling in Wired and Wireless Networks (PEMWN'2019).
},
publisher = {IEEE},
abstract = {Edge computing technologies and integrated archi- tectures have been deployed to accommodate Internet traffic growth. These architectures include facilities (cloudlets, micro DCs) to cache and serve contents close to consumers. Resulting systems adapt to observed request/consumption patterns by allowing cloudlet coordination for content caching/dissemination. This paper presents a novel analytical model of transient dy- namics of the cloudlets set. The model is used to study system convergence, stability and delivered content locality. Results from this model are validated via simulations.},
keywords = {},
pubstate = {forthcoming},
tppubtype = {inproceedings}
}
Edge computing technologies and integrated archi- tectures have been deployed to accommodate Internet traffic growth. These architectures include facilities (cloudlets, micro DCs) to cache and serve contents close to consumers. Resulting systems adapt to observed request/consumption patterns by allowing cloudlet coordination for content caching/dissemination. This paper presents a novel analytical model of transient dy- namics of the cloudlets set. The model is used to study system convergence, stability and delivered content locality. Results from this model are validated via simulations.
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