| Wireless mobile networks enable people to realize the dream that any information could be collected at anytime anywhere. In wireless mobile networks, due to the mobility of mobile users, their points of attachment to the networks change constantly. Therefore, how to track mobiles effectively and economically and how to provide them with real-time, low cost, high quality and optimal services, i.e. mobility management, become a international challenging frontier. Undoubtedly, mobility management is significant for mobile communication networks to work effectively and efficiently.In mobile communication networks, mobility management consists of location management and handoff management. This paper focuses on the former. The current location management scheme used in mobile communication networks requires that location update be initiated immediately whenever a mobile crosses the boundaries of location areas. Obviously, this scheme wastes the system's resources substantially since a lot of location updates may be not necessary to users with a low... |