An efficient hierarchical scheme for locating highly mobile users
Evaggelia Pitoura, Ioannis Fudos · 1998
To accommodate the increase in user population in future personal communication systems, hierarchical architectures of location databases have been proposed. In this paper, a scheme based on forwarding pointers is presented, that reduces the cost of the overall network and database traffic generated by frequent location updates in such hierarchical architectures. To reduce the number of forwarding pointers that need to be traversed to locate a user, auxiliary caching techniques are presented. Various conditions for purging the chain of forwarding pointers and updating the database are also introduced. Special care is given so that the scheme correctly supports the concurrent execution of updates and lookups. The applicability of the scheme and the performance of the caching techniques are demonstrated through a number of experiments for a range of call to mobility ratios and for a variety of moving and calling behaviors. 1 Introduction Advances in wireless telecommunications and in t...