A Distributed GLR Scheme for 3G Cellular Networks

The Gateway Location Register (GLR) in the Universal Mobile Telecommunication System (UMTS) Core Network is a national node between the VLR and/or SGSN and the HLR. It handles location management created by roaming users in visited network, usually located far away from users' home network, without involving the HLR in every change of location areas (LAs). However, when the number of roaming subscribers increases in a visited network, the centralized GLR may become a bottleneck of the system, which results in degrading system performance and quality of service. In this paper, we present a novel distributed GLR scheme for 3G cellular networks where the location management signaling overhead is evenly distributed to each VLR in the visited network. Analytic results show that our distributed scheme outperforms the traditional centralized GLR scheme. In addition, the system's robustness is greatly enhanced in our proposed system.