Dynamic location management with variable size location areas

Abstract

This paper introduces a dynamic location management algorithm with variable size location areas (LAs), which helps in reducing location update (LU) cost and hence total location management cost. Basically there are two types of location management strategies - Static and Dynamic. In the static strategy (used in GSM), LAs consist of static and arbitrarily defined collections of cells, which do not take into account individual subscriber's mobility pattern and hence these LAs remain same for all the subscribers. Since mobility pattern of an individual subscriber may differ significantly, this approach is far from optimal. Proposed location management algorithm uses the mobility history of individual subscribers to dynamically form individualized LAs based on his previous movements from cell to cell. It defines the size of LAs based on subscriber's speed and call arrival probability. An activity-based mobility model is developed to test the proposed algorithm and the performance of this algorithm is compared with other algorithms, like fixed location strategy, grid-based location management strategy and dynamic location management algorithm. Overall, the proposed algorithm incurred significantly lower location management cost, in terms of signaling messages generated, as compared to all other algorithms.