Topology Reconfiguration with Successive Approximations

Recent technologies have enabled the formation of point-to-point directional wireless networks that are capable of dynamic changes in the network topology. The process of dynamically changing the network topology in response to changes in available link capacities and load demands is called topology control. Topology control involves the computation of new topologies to dynamically optimize network performance under changing traffic conditions and then carrying out the physical reconfiguration process to implement the target topology. This paper studies the process of topology reconfiguration by using the packet drops that occur during this process as a cost metric. It is shown that the reconfiguration cost is minimized when the target topology is implemented in a series of intermediate steps (successive approximations). It is also shown that a topology computation algorithm that results in lower overall packet drops can be obtained by including the reconfiguration cost in the objective function along with the typical objective of congestion minimization. Simulations are used to evaluate the performance of various topology control algorithms when the objective function includes the reconfiguration cost.