Elimination of generalized ping-pong effects using triple-layers of location areas in cellular networks

Location-areas is a popular location management scheme in cellular networks. In the location areas scheme, a service area is partitioned into location areas, each consisting of contiguous cells. A mobile terminal updates its location whenever it moves into a cell that belongs to a new location area. However, no matter how the location areas are designed, the ping-pong location update effect exists when a mobile terminal moves back and forth between two location areas. The paper defines a new kind of ping-pong effect, referred to as the generalized ping-pong effect, and shows that it accounts for a nonnegligible portion of the total location update cost. Although several strategies have been proposed to reduce the ping-pong effect in the literature, they either eliminate no generalized ping-pong effect or introduce a larger paging cost. This paper proposes a triple-layer location management strategy to eliminate the generalized ping-pong effect, therefore greatly reducing the total location update cost. Simulation results show that the triple-layer strategy outperforms the existing schemes designed to reduce the ping-pong effect.