Client location tracking in ubiquitous information service network

The objective of this paper is to present a feasible and efficient methodology that improves client mobility management under ubiquitous information service network. We base our system on the Open Integrated Service Network Architecture and propose a hybrid infrastructure with facilities of both a centralized Network Management Center (NMC) and a distributed Home Base Node (HEN). We also have criteria for choosing a HEN with minimum cost by computing the expected registration cost and location tracking cost according to users characteristics and called frequencies. Running a simulation, results show that our methodology is able to save up to 40% of the cost comparing to that of IS-41 when the value of Call-Mobility Ratio (CMR) is in the range of (1, 100), which means either clients are called with high frequencies or are moving with low mobilities. As the value of CMR goes down to the range of (0.01, 1), which means either clients are called with low-frequencies or are moving with high mobilities we may save up to 50% cost.