A New Hashing and Caching Approach for Minimizing Overall Location Management Cost in Next-Generation Wireless Networks

This paper proposes a new hashing and caching strategy (NHC) in order to reduce the overall location management cost in wireless mobile networks. It uses caches whose up-to-date information is responsible for dropping this cost and these caches are updated not only at call arrival time from the calling Mobile Terminals (MTs) but also at call receiving time to those MTs, and even at location registration time. To achieve load balancing among replicated Home Location Registers (HLRs), hashing technique is used and this load is also affected by the up-to-date cache information. The analytical modeling and numerical results show that our proposed method more frequently prepares the caches with up-to-date information with the increase of average call arrival rate, average call receiving rate, and even with MT’s increased mobility rate. This increases the probability of finding called MT’s location as well as hit ratio in the caches. As a result, the overall location management cost including load on a particular location server (HLR) are minimized considerably than all other previous approaches. Keywords—Location management, location registration, call delivery, cache, hashing function.