在無線通訊系統中位置管理(Location Management)是很重要的議題。本論文探討行動通信網路及行動IP網路之位置管理策略，行動通信網路之位置管理策略以本籍位置記錄器(Home Location Register)的配置來分類可分為集中及分散式管理策略，本論文提出一種集中式位置管理策略名為PFCV，此方法可以降低更改本籍位置記錄器的耗費(cost)，避免本籍位置記錄器成為信號網路中的瓶頸，此方法除了開機及來話外皆不會存取本籍位置記錄器。
然而隨著行動服務的大量使用，因註冊產生的訊務大幅增加，本籍位置記錄器最有可能成為信號網路中的瓶頸。本論文提出分散式本籍位置記錄器策略名為KPFDHLR，此策略大幅減少本籍位置記錄器資料庫存取延遲，避免多個本籍位置記錄器同時必須更動的缺失並且保證指標鏈(pointer chain)的長度不會超過K，因此可以提供高品質的服務。

接著探討行動IP(mobile IP)網路之位置管理策略，以廣域的眼光來看，當行動節點(Mobile Node)所處的網路與本籍代理器 (Home Agent)及應對節點(Corresponding Node) 離的很遠時，每一次交遞可能會產生過大的負荷及封包遺失，我們善用前向指標(pointer forwarding) 的技術，改善上述缺失，當行動節點時常移動但很少接收封包時，本文所提的方法比標準的行動網際網路協定(Mobile IP)方法耗費還少。

本論文探討多個無線通訊位置管理方面的策略：我們利用前向指標的技術將行動用戶行經的臨近註冊區域串連起來，如此就不用跟遠方的本籍位置記錄器或本籍代理器不斷的註冊，另外我們利用分散式本籍位置記錄器的方式改善集中式本籍位置記錄器瓶頸問題，此外我們也提出”首訪客位置記錄器”(Heading VLR)的概念，經由跟”首訪客位置記錄器”註冊的動作，使指標鏈結長度不致太長，因此可提供好的服務品質。

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.

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