Due to the dynamic nature of mobile ad hoc network (MANET), the quality of service (QoS) requires several improvements. The present paper comes within the framework of research to optimize QoS in MANET. In this paper, we propose a novel version of OLSR based on the clustering approach which is inspired from Lin and Chu heuristic and adapted to be implemented in OLSR. We studied its stability and we compared its performances to those of standard OLSR. The metrics we used in evaluating network performances were average end-to-end delay, control routing overhead, and packet delivery ratio. Experimental results show that our alternative significantly reduces the traffic reserved to monitoring the network, which positively influences other performances such as throughput, delay, and loss. 1. Introduction MANETs are mobile radio networks with no infrastructure, allowing a quick and easy implementation. They may also be coupled to a LAN to extend the coverage of existing infrastructure. Nodes can appear, disappear, and move independently from each other. The network topology is scalable. Terminals can communicate within the limit of its radio power. A diagram of multihop communication is necessary to allow two remote nodes to communicate. In this communication scheme, each terminal can be used as router to relay other terminals communications. The configuration of these multihop roads is carried out by routing protocol. To be effective, these routing protocols must consider the intrinsic characteristics of the network (topology changing), terminals (memory size and computing capacity limited), and the medium of communication (bandwidth limited, interference). Many of the routing protocols for ad-hoc networks are classified as either proactive or reactive routing protocols. Proactive routing protocols try to collect information about the MANET through proactive exchange of messages about their local topology. These protocols reach rapidly their limits when increasing density and mobility of nodes. However, reactive protocols find a route on demand by flooding the network with route request packets and require an important delay to find and to use the route that links up two nodes. Currently there are many routing protocols for each type of network. However, even this efficiency on small and medium size networks, neither of them can be used on large scales because they generate too much control traffic or would require too large routing tables. One solution commonly proposed for routing on large scales is to introduce a hierarchical routing by grouping
References
[1]
I. G. Shayeb, A. R. H. Hussein, and A. B. Nasoura, “A survey of clustering schemes for Mobile Ad-Hoc Network (MANET),” American Journal of Scientific Research, no. 20, pp. 135–151, 2011.
[2]
V. Katiyar, N. Chand, and S. Soni, “A survey on clustering algorithms for heterogeneous wireless sensor networks,” International Journal of Advanced Networking and Applications, vol. 2, no. 4, pp. 745–754, 2011.
[3]
A. Ephremides, J. E. Wieselthier, and D. J. Baker, “Design concept for reliable mobile radio networks with frequency hopping signaling,” Proceedings of the IEEE, vol. 75, no. 1, pp. 56–73, 1987.
[4]
M. Jiang, J. Li, and Y. Tay, “Cluster Based Routing Protocol (CBRP). DRAFT draft-ietf-manet-cbrp-spec-01.txt, IETF,” 1999.
[5]
M. Gerla and J. Tsai, “Multicluster, mobile, multimedia radio network,” Wireless Networks, vol. 1, no. 3, pp. 255–265, 1995.
[6]
C. C. Chang, H. K. Wu, W. Liu, and M. Gerla, “Routing in clustered multihop, mobile wireless networks with fading channel,” in Proceedings of IEEE Singapore International Conference on Networks (SICON ’97), pp. 197–212, Singapore, April 1997.
[7]
P. Basu, N. Khan, and T. D. C. Little, “A mobility based metric for clustering in mobile and ad hoc networks,” in Proceedings of International Conference of Distributed Computing Systems Workshop (ICDCSW '01), pp. 413–418, Phoenix, Ariz, USA, April 2001.
[8]
Y. Fernandess and D. Malkhi, “K-clustering in wireless ad hoc networks,” in Proceedings of the Second International Workshop on Principles of Mobile Commerce (POMC '02), pp. 31–37, October 2002.
[9]
A. D. Amis, R. Prakash, T. H. P. Vuong, and D. T. Huynh, “Max-min D-cluster formation in wireless Ad Hoc networks,” in Proceedings of IEEE Conference on Computer Communications (INFOCOM ’00), vol. 1, pp. 32–41, Anchorage, Alaska, March 2000.
[10]
C. A. Santivá？ez, B. McDonald, I. Stavrakakis, and R. Ramanathan, “On the scalability of ad hoc routing protocols,” in Proceedings of the IEEE Infocom, pp. 1688–1697, June 2002.
[11]
B. J. Kwar, N. O. Song, and L. Miller, “On the scalability of ad hoc networks,” in Proceedings of the IEEE Communication letters, 2004.
[12]
X. Cheng, M. Ding, D. H. Du, and X. Jia, “Virtual backbone construction in multihop ad hoc wireless networks,” Wireless Communications and Mobile Computing, vol. 6, no. 2, pp. 183–190, 2006.
[13]
H. C. Lin and Y. H. Chu, “A clustering technique for large multihop mobile wireless networks,” in Proceedings of the Vehicular Technology Conference (VTC ’00), Tokyo, Japan, 2000.
[14]
A. Qayyum, L. Viennot, and A. Laouiti, “Multipoint relaying: an efficient technique for flooding in mobile wireless networks,” Technical Report Research Report RR-3898, INRIA, 2000.
[15]
P. Jacquet, P. Mühlethaler, T. Clausen, A. Laouiti, A. Qayyum, and L. Viennot, “Optimized link state routing protocol for ad hoc networks,” in Proceedings of the 5th IEEE Multi Topic Conference (INMIC '01), 2001.
[16]
T. Clausen and P. Jaquet, “RFC, 3626 optimized link state routing protocol,” October 2003.
[17]
R. Khandekar, G. Kortsarz, and V. Mirrokni, “Advantage of overlapping clusters for minimizing Conductance,” in Proceedings of the 10th Latin American international conference on Theoretical Informatics (LATIN '12), pp. 494–505, Springer, Berlin, Germany, 2012.
[18]
A. Hajami, K. Oudidi, and M. Elkoutbi, “An enhanced algorithm for MANET clustering based on Multi hops and Network Density,” in Proceedings of the Dixième Conférence Internationale sur les Nouvelles Technologies et la Repartition, Notere, Tozeur, Tunisie, May–July 2010.
[19]
A. Hajami, K. Oudidi, and M. Elkoutbi, “A distributed key management scheme based on Multi Hop Clustering Algorithm for MANET,” International Journal of Computer Science and Network Security, vol. 10, no. 1, pp. 39–49, 2010.
