2018
Thomas Clausen; Jiazi YI; Juan Antonio Cordero; Yuichi Igarashi
Use 'em or Lose 'em: On Unidirectional Links in Reactive Routing Protocols Journal Article
In: Elsevier Ad Hoc Networks, vol. 73, 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://www.sciencedirect.com/science/article/pii/S1570870518300325
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},
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}
}
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.
2017
Thomas Clausen; Jiazi Yi; Ulrich Herberg
Lightweight On-demand Ad hoc Distance-vector Routing-Next Generation (LOADng): Protocol, Extension, and Applicability Journal Article
In: Elsevier Computer Networks, vol. 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 = {Elsevier 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}
}
2015
Jiazi Yi; Thomas Clausen; Ulrich Herberg
Depth-First Forwarding for Unreliable Networks: Extensions and Application Journal Article
In: IEEE Internet of Things Journal, vol. 2015, no. 06, 2015.
Abstract | Links | BibTeX | Tags: DFF, LLN, LOADng, 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, SOGRID},
pubstate = {published},
tppubtype = {article}
}
2014
Jiazi Yi; Thomas Clausen
Collection Tree Extension of Reactive Routing Protocol for Low-Power and Lossy Networks Journal Article
In: Hindawi International Journal of Distributed Sensor Networks, vol. 2014, no. Article ID 352421, pp. 12, 2014.
Abstract | Links | BibTeX | Tags: LLN, LOADng, 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, SOGRID},
pubstate = {published},
tppubtype = {article}
}
Juan Antonio Cordero; Jiazi Yi; Thomas Clausen
An Adaptive Jitter Mechanism for Reactive Route Discovery in Sensor Networks Journal Article
In: Sensors, vol. 14, no. 8, pp. 14440, 2014, ISSN: 1424-8220, (http://www.mdpi.com/1424-8220/14/8/14440).
Abstract | Links | BibTeX | Tags: Jitter, LOADng
@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, LOADng},
pubstate = {published},
tppubtype = {article}
}