الفهرس 
Wireless Communication NetworksOnly 14 pages are availabe for public view
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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.