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Abstract Today’s world is the world of connectivity. Therefore, the notion of mobility is emerging in many forms and applications. Increasingly many users are not tied to a fixed access point but instead use mobile hardware such as dial up services or wireless communications. Furthermore mobile data move among network locations is emerging as a new form of building distributed network. In order to deliver mobile data to certain users in the network, locating users, as they move from one place to another, is a key issue that allows unrestricted mobility, yet poses several challenging constraints to the network designers. So the term mobility management arises. Mobility management enables telecommunication networks to locate moving users for call delivery and to maintain connections as the user is moving into a new service area. Thus, mobility management supports mobile users, allowing users to move freely while simultaneously offering them incoming calls and supporting calls-in-progress. Location management is a part of the mobility management process, which is responsible to locate moving users through the network The goal of the location management process is to minimize its cost, which is augmented to two different processes, searching for its location (Paging), which is initiated by the network, and reporting the user’s location (Location Update), which is initiated by the mobile user itself. A Direction Based Location update Scheme with Line Paging strategy is presented earlier which updates the mobile user’s location only when it changes its direction and searches for the user in that direction too.In this research, an enhanced Direction Based Location Update scheme is presented and combined with a predictive line paging strategy. The use of prediction of the mobile users’ location leads to performing less searching (pagings) to locate the user in order to minimize the location management total cost. An implementation for this enhancement is experienced over both random walk and random waypoint mobility patterns. Results obtained proved a reduction in the overall cost with an average of 35% compared to the Direction Based Location update scheme with Line Paging strategy for users moving with random waypoint mobility pattern, while a slight increase in the cost with an average of 3% has been noticed for users moving with a complete random walk mobility pattern. Further, an Adaptive Direction Based Location update is proposed. In which a periodic location update messages were added in order to increase the accuracy of predicting the location of mobile users. The Adaptive Direction Based Location update scheme is applied along with predictive line paging in order to reduce the total cost of the location management process. It is applied with different sets of cost coefficients for location updates and pagings. The first experiment sets the cost of sending an update message half of the cost of paging one cell of the wireless network and showed a reduction in the cost with an average of 19% compared to the Direction Based Location update scheme with Predictive Line paging strategy, while reducing the cost with an average of 35% compared to the Direction Based Location update scheme with Line Paging strategy. The second experiment, which sets the cost of sending an update message equal to the cost of paging one cell of the wireless network, showed a reduction in the cost with an average of 19% compared to the Direction Based Location Update with Predictive Line Paging strategy and 32% compared to the Direction Based Location update scheme with Line Paging strategy. Finally analytical equations were driven for both Direction Based Location update scheme with Line Paging strategy and Direction Based Location update scheme with Predictive Line Paging strategy showing approximate results for the simulation model. |