6.7 Conclusion

Clustering is still an ongoing research area, and the literature in this area is rich. For example, McDonald and Znati ^[23] introduce a clustering routing technique for ad hoc wireless LANs, where the network is partitioned into clusters of nodes mutually reachable with a certain specified probability for a certain time. Simulation results support the inherent adaptability and stability of the protocol. Hierarchical clustering and routing techniques have been and continue to be under investigation. ^[24], ^[25] A strict hierarchical clustering and routing technique, which was designed for multimedia support in large mobile wireless networks, is presented in Ramanathan and Steenstrup. ^[26] Another hierarchical clustering and routing technique, NTDR, ^[27] was designed for the tactical environment, where a backbone network exists between cluster heads.

^[23]McDonald, B. and Znati, T., A mobility based framework for adaptive clustering in wireless ad hoc networks, IEEE J. Selected Areas Commun., 17 (8), 1–20, 1999.

^[24]Lauer, G.S., Hierarchical routing design for SURAN, IEEE International Communications Conference (ICC), June 1986, pp. 93–102.

^[25]Lee, W.C., Topology aggregation in hierarchical routing in ATM networks, ACM Sigcomm '95, Corp. Commun. Rev., 25 (2), 82–92, 1995.

^[26]Ramanathan, R. and Steenstrup, M., Hierarchically-organized multihop mobile wireless networks for quality-of-service support, ACM/Blatzer Mobile Networks Appl. J., 3 (1), 101–119, 1988.

^[27]Zavgren, J., NTDR mobility management protocols and procedures, Proc. IEEE Military Communications Conference (MILCOM) '97, November 1997.