Optimal location update: scheme to combat database failure for PCS networks

When location information in the home location register (HLR) is corrupted or obsolete, the new arriving calls to the portable may be lost. In order to minimize the effect of such a HLR mobility database failure, a location update scheme which is called period location updating is proposed, and a cost analysis is performed. Analytical results for the failure recovery time distribution and time average number of call losses, which are crucial for cost analysis, are presented. The optimal location update period is found analytically and can be expressed as a function of other traffic parameters. This optimal choice of location update period lays the foundation for adaptively adjusting the location update period in PCS failure restoration