ONE of the challenges facing mobile computing is the tracking of the current location of users—the area of location management. In order to route incoming calls to appropriate mobile terminals, the network must from time to time keep track of the location of each mobile terminal.
Mobility tracking expends the limited resources of the wireless network. Besides the bandwidth used for registration and paging between the mobile terminal and base stations, power is also consumed from the portable devices. Furthermore, frequent signaling may result in degradation of Quality of Service (QoS), due to interferences. On the other hand, a miss on the location of a mobile terminal will necessitate a search operation on the network when a call comes in. Such an operation, again, requires the expenditure of limited wireless resources. The goal of mobility tracking, or location management is to balance the registration (location update) and search (paging) operation, so as to minimize the cost of mobile terminal location tracking.
Location Management in Mobile Computing Systems