18-07-2014, 10:15 AM
Mobility Management
Mobility Manage.pptx (Size: 46.11 KB / Downloads: 19)
Introduction
Wireless mobile networks are expanding rapidly all over the world to provide information services for people and machines on the move.
Wireless network systems are fundamentally different from fixed networks in the way that connections between network and subscribers are established and maintained.
Components
Location Management: Location management is a two-stage process that enables the network to discover the current attachment point of the mobile user for call delivery. The first stage is location registration. The second stage is call delivery.
Handoff Management: Handoff management enables the network to maintain a user’s connection. The three-stage process for handoff first involves initiation, second stage is new connection generation, and last is data flow control.
Location Tracking Strategies
Fixed LAs : This is the most commonly used mobility management scheme in the current second generation cellular networks. The service area is divided into a set of LAs.
2. Several PAs in Each LAs : This approach suggests to subdivide each LA into a number of PAs of the same size. The LU remains the same.
3. Overlapped Las : To prevent the oscillation effect of LUs when a mobile happens to be traveling along the border of two LAs.
. User Grouping and Multilayer Las : Users are classified according to their degree of mobility and location of residence and work-place. The service area is divided into several sets of LAs.
5. Optimal Paging Algorithm : This study established the fundamental theory of optimal sequential paging.
6. The Alternative Location Strategy : The main goal of this approach is to reduce LUs by taking advantage of the people’s highly predictable mobility patterns.
Periodic Timer-Based Approach: This is conventional method of time-based strategies. In this strategy, a user updates is location periodically at fixed time interval without regard to its mobility and call conditions. The whole service area is divided into a number of PAs.
Adaptive Paging Algorithms : This scheme uses a fixed time interval for LUs and a two-step paging procedure. A multiple-step paging procedure polls a user by starting from the PA .