A comparative study on distributed location management strategies in wireless networks

Location management is an essential process in future mobile communication networks. An important issue is an efficient management of the location database. In this paper, the next generation mobile communication networks are proposed to integrate with a TINA-compliant architecture enabling to handle that kind of mobile-specific processes. We consider a distributed location database architecture for location management performing the following strategies: HLD (home location database only), HLD-VLD (HLD with a visited location database), or VLD-CLD (HLD and VLD with a cache location database). This paper discusses design, modelling and the comparison of the mentioned distributed location management strategies. The performance measures used for comparison are communication cost (signalling messages), computational cost (database accesses) and average total cost. For the performance analysis, we assume that the cost of updating a cache pointer and a user profile at CLD/VLD is equal. Results show that the combination of replication with caching scheme (VLD-CLD) performs better than the replication scheme (HLD-VLD) for a very wide range of call-to-mobility ratio (CMR).