Tradeoff analysis for location update and paging in wireless networks

Location management plays the central role in providing ubiquitous communications services in the future wireless mobile networks. Location update and paging are commonly used in tracking mobile users on the move, location update is to update a mobile user's current location while the paging is used to locate a mobile user, both will incur signaling traffic in the wireless networks. The more frequent the location updates, the less paging in locating a mobile user, thus there is a tradeoff in terms of signaling cost. Tradeoff analysis of this type has been carried out in the past under exponential assumption for certain time variables. In this paper, we relax all assumptions and analytically derive the average number of location updates during the inter-service time for a movement-based location update scheme under fairly realistic assumption, a number which are required for all tradeoff analysis. We then carry out case studies and numerically demonstrate that the cost function in our analysis indeed has a unique global optimal movement threshold.