Placing and maintaining a core node in wireless ad hoc networks

Wireless ad hoc networks are characterized by several performance metrics, such as bandwidth, transport, delay, power, etc. These networks are examined by constructing a tree network. A core node is usually chosen to be the median or center of the multicast tree network with a tendency to minimize a performance metric, such as delay or transport. In this paper, we present a new efficient strategy for constructing and maintaining a core node in a multicast tree for wireless ad hoc networks undergoing dynamic changes, based on local information. The new core (centdian) function is defined by a convex combination signifying total transport and delay metrics. We provide two bounds of O(d) and O(d + l) time for maintaining the centdian using local updates, where l is the hop count between the new center and the new centdian, and d is the diameter of the tree network.We also show an O(n log n) time solution for finding the centdian in the Euclidian complete network. Finally, an extensive simulation for the construction algorithm and the maintenance algorithm is presented along with an interesting observation.