User profiles and their replication for reduction of HLR accesses and signalling load

The widespread deployment of mobile personal communication services will lead to a tremendous increase in the number of real time updates and queries to the network databases. The centralised HLR in GSM can be a potential bottleneck. Most users have regular calling and mobility patterns, and the mobility profile of such users can be used to reduce location updates. By replicating the location of the called mobiles at the source-MSC/VLR, HLR queries can be reduced. This paper studies the cost of replicating user mobility profiles. A scheme for replicating the profiles, exploiting the regular calling patterns of users, is also presented. The replication scheme is analysed and compared with the GSM method. It is shown that considerable reduction in HLR accesses and signalling cost can be achieved at the expense of extra memory at the MSC/VLR.