On The Recovery Performance of Single- and Multipath OLSR in Wireless Multi-Hop Networks

Inès Doghri (1) , Laurent Reynaud (1) , Isabelle Guérin-Lassous (2, 3)

1 Orange Labs [Lannion]
2 RESO - Protocols and softwares for very high-performance network
3 LIP - Laboratoire de l'Informatique du Parallélisme

In this paper, we study and improve the recovery properties of single and multipath routing strategies when facing network failure situations. In particular, we focus our study on two MANET routing protocols: OLSR and its multipath extension MP-OLSR. In various wireless multi-hop network environments, especially in multiple chain topologies, we define and seek to evaluate the latency introduced by these protocols to find a new path after a link failure. Theoretical estimations and simulation results show that, under dual chain-topologies, this latency can be too long and incompatible with the needs of loss and delay constrained applications. As the source nodes cannot detect link failures immediately because of the delay incurred by the well-known nature of link state protocols in general, and of OLSR Topology Control (TC) messages in particular, these nodes keep sending packets along broken paths. We thus study the inconsistencies between the actual network topology and the nodes' own representation. After analyzing the consequences of this long latency, we seek to alleviate these problems with the introduction of adapted mechanisms. We propose three new different schemes and accordingly extend the original OLSR and MP-OLSR protocols in order to decrease the expected latency and improve the protocol performance. Simulation results show a steep decrease of the latency when using these new schemes in dual chain-topologies. We also discuss these results in terms of packet loss, end-to-end delay and overhead.

Mots clés: ad hoc networks; multipath routing; link state protocols; fault tolerance

Domaines: Réseaux et télécommunications [cs.NI]

Inès Doghri, Laurent Reynaud, Isabelle Guérin-Lassous. On The Recovery Performance of Single- and Multipath OLSR in Wireless Multi-Hop Networks. Third International ICST Conference on Ad Hoc Networks, ADHOCNETS 2011, Sep 2011, Paris, France. pp.239, ⟨10.1007/978-3-642-29096-1⟩. ⟨hal-00708684⟩