This Article describes mobility management for the third-generation mobile network .focus is given on the evolution from General Packet Radio Service (GPRS) to Universal Mobile Telecommunication System (UMTS). In this evolution, the UTRAN radio access network which has been introduced, and radio-related managements moved from the core network to UTRAN. We elaborate on how this architecture change the affects the mobility which management functionality, including the attach & location update, detach procedures, serving relocation of radio network controller and intersystem change between GPRS and UMTS.
The dynamic Hierarchical Mobility Management Strategy for Mobile IP Networks :
1 of the major challenges for the wireless network
design is the efficient in management the mobility , which can be
addressed globally (macromobility) and locally (micromobility).
Mobile Internet protocol (IP) is a commonly accepted standard
to address global mobility of mobile hosts (MHs). It requires
the MHs to register with the home agents (HAs) whenever
their care-of change the addresses . However such registrations may
cause excessive signaling traffic and delay in long service . To solve
this problem, the hierarchical mobile IP (HMIP) protocol was
proposed to the employ the hierarchy of foreign agents FAs and the
gateway FAs that is GFAs to localize registration operations. However,
the performance of the system is critically affected by the selection of
GFAs and their reliability.
Concepts of Mobility Management :
In order to track the MSs, the cells (i.e., BTSs/Node Bs) in GPRS/UMTS service area are partitioned into different groups. To deliver services to an MS, the cells in the group covering the MS will page the MS to establish the link of the radio. The location change of the MS which is detected . The cells broadcast their identities cell. The MS periodically listens to the broadcast identity of the cell , and compares it with the cell identity stored buffer in MS’s . If the comparison indicates that the location which has been changed, then the MS sends the location update the message to network.
THE CURRENT fast increasing demand for wireless access to the Internet applications which is fueled by the remarkable success of the wireless communication networks and explosive growth of the Internet. The future generation wireless networks target to provide users with high-speed Internet access and multimedia services besides voice. possible for mobile users to access the Internet applications that are predominantly based on Internet protocol.
Dynamic Location Update Schemes :
•Time Based : A mobile terminal updates in every T time units
•Movement-Based: A mobile terminal counts the number of boundary crossings and performs the update when a threshold is exceeded example M=6
–Forwarding the pointers may be considered as a variation of it
•Distance Based : A mobile terminal tracks the distance (in terms of RAs) it has moved since the last update
–Update is performed when the distance threshold is exceeded
–The mobile terminal needs some knowledge of the network topology
–Local Anchor can be considered as a variation of it.
Q1: What are the 2 important points to ensure constant connectivity ?
Ans : 1. Infrastructure management that connects two or more cells or networks.
2. Location management and registration management by handoff when mobile devices move from one cell to another cell.
Q2: how can we improve The performance of the DHMIP scheme.
Ans: It can be improved by the IP paging and loop removal
Q3: Explain Replicating Location Information based on Hierarchical Organization ?
Ans: This is A tree of location registrars:
–A location registrar (LR) that is a leaf node in the tree has information on all the mobile users in its RA
–A non-leaf LR replicates location information in all the location registrars in the subtree rooted to it.
–The root registrar in the tree has information on all the mobile users in the system.
Q4: What is Mobile Terminal Paging ?
Ans: A process by which the network determines the exact location of a particular mobile terminal
•Polling cycle or search iteration:
–Polling signals sent over a downlink control channel where the mobile terminal is likely to be
–If a reply is received before a timeout, the polling ends; otherwise, a new group of cells is chosen
–A call is dropped when the mobile terminal is not located within an allowable time constraint
–“ the maximum paging delay” is the maximum number of polling cycles allowed to locate a mobile terminal
•The Paging cost is proportional to number of polling cycles as well as number of cells polled in each cycle .
Q5:What is the full form of BTS ?
Ans: BTS is Base Transceiver Station.