Abstract
This thesis describes current and proposed protocols for mobility management for Public Land Mobile Network (PLMN)-based networks and Mobile Internet Protocol network. First, a series of location management algorithms for Personal Communication Systems (PCS) implemented over a PLMN network are provided. The discussion of PLMN network location management issues in this thesis were categorized into both centralized and distributed HLR solutions. The Pointer Forwarding with Cooperative VLRs (PFCV) User Location Strategy was proposed to reduce location update cost and prevent HLR from becoming a signal bottleneck in the signaling network. This strategy distributes most of the user location loading to the VLRs. Moreover, the PFCV saves network resources because it eliminates unnecessary location updates since it never updates the HLR except when it receives a call or the mobile is initiated. However, the heavy signaling traffic generated by PCS registration is expanding rapidly and the HLR may become the bottleneck due to the increased use of wireless services. This thesis extends the Local Anchoring Strategy by distributing HLRs in several regions to relax single HLR bottleneck problem. The proposed Distributed Local Anchoring Strategy (DAS), eliminates the cost of updates multiple HLRs, vastly reducing the database access delay. The performance of the strategy is numerically analyzed. Results demonstrate that the DAS strategy can considerably reduce call delivery time. The extended DAS strategy,named K-Step Pointer Forwarding Strategy with Distributed HLR (KPFDHLR), was proposed. This strategy guarantees that the pointer chain length never exceeds K. Its performance is studied by numerical analysis. Followed by a discussion of proposed Mobile IP Version 6 (MIPv6) location management strategy. In wide area deployment, heavy signaling traffic and the handoff latencies due to mobile IP registration could be high if the distance between the visited network and the home network of a Mobile Node is large. Also, base stations with small cells yield frequent handoffs, and requiring a registration with a distant Home Agent and Correspondent Nodes for each such local handoff increases overheads and further aggravates packet loss. This study extends the Pointer Forwarding strategy to allowing Mobile Nodes to use a cascaded tunneling scheme in a mobile IP network, called Pointer Forwarding MIPv6 Mobility Management (PFMIPv6) strategy. This approach reduces the cost of updating distant Home Agent and Correspondent Nodes, which greatly reduces the number of signaling messages in the network. Furthermore, the tunneling chain of a Mobile Node is determined dynamically with no need for preliminary definitions of static anchors or regions. The results of this work demonstrate that the new strategy yields lower average costs than the MIPv6 method, when MNs move fast, but packets are rarely received.