Rate of Degradation of Centralized Optimization Solutions and its Application to High Performance Domain Formation in Ad Hoc Networks

K. Manousakis, J. S. Baras, A. J. McAuley, R. Morera

MILCOM 2004, Monterey, California, October 31 - November 3, 2004.

 

Abstract

Future military systems such a FCS and WIN-T require a robust and flexible nenvork that supports thousands of ad hoc nodes; therefore, we must ensure the scalability of networking protocols (e.g., routing, security and QoS). The use of hierarchy is a powerful solution to the scaling problem, since it allows networking protocols to operate on a limited number of nodes, as opposed tu the entire network. We have proposed an automated solution to dynamically create and maintain such hierarchy bused on a combination of global optimization algorithms [ I ] and local distributed maintenance protocols 121. Global optimization clearly improves peqormance in a static network but, it is unclear how effective it is in a dynamic ad hoc environment. In this paper, we analyze how the hierarchy created deteriorates from the optimal as nptwork conditions change. We show that the fragility of the optimizationdepends on the particular cost function and the number of merrics that change. More important, we show, for thefirsf time, that global optimization can remain effective for long periods with good cost functions, even in large dynamic ad hoc networks (where metrics may chmge rapidly due to node mobility and links making and breaking).