IPv6(Internet Protocol Version 6) [6]在位址格式中新增加了anycast[5]的位址。在傳送anycast的封包時，若多個內容相同的伺服器擁有同一個anycast的位址，該anycast封包是送到離client最接近的伺服器中，因為離client最接近的伺服器，並不代表是delay time最小的伺服器，因此在這篇論文中，我們發表了一個針對anycast封包的通訊協定。在這個通訊協定中包含了兩個子協定。第一個子協定為建立routing table的子協定；第二個子協定為封包傳送的子協定。在建立routing table的子協定中，我們提出了一個新的方法，稱之為最短延遲時間路徑(minimum delay path method)。根據最短延遲時間路徑，我們可以得到從router到目的端最短延遲時間的路徑，若根據此路徑來傳送封包，則可得到比傳統方法較佳的QoS(Quality of Services)。在封包傳送的子協定中，我們提出一個最小延遲及負載平衡(minimum delay and load balancing)的方法。此方法最主要是根據目前所有伺服器的負載情況，及連接該伺服器的最短延遲時間路徑，來決定其中最適合傳送的伺服器及路徑。根據實驗的結果顯示出我們提出的方法可有效減少end-to-end delay及增加網路的throughput。

Anycast is a new communication service defined in IPv6 (Internet Protocol Version 6) [6]. An anycast message is the one that should be delivered to the 'nearest' member in a group of designated recipients. The ‘nearest’ is not always the ‘best’ member. In this paper, we propose a routing protocol for anycast message. It is composed of two subprotocols: the routing table establishment subprotocol and the packet forwarding subprotocol. In the routing table establishment subprotocol, we propose a mininum delay path method (MDP). We get a minimum delay path from router to destination by MDP. In the packet forwarding protocol, we propose a minimum delay and load balancing method (MDLB). We dispatch traffic load to a server with minimum delay and light load by MDLB. The performance has demonstrated the benefits of MDP and MDLB in reducing end-to-end delay and increasing throughput of network.

摘要 i
Abstract ii
第一章 簡介 1
第二章 我們的方法 12
2.1 Routing Protocol概論 12
2.2 Routing Table Establishment Subprotocol 14
2.2.1 Candidate entries的建立 14
2.2.2 Updating Algorithm of TRACE message 15
2.2.3 Updating Algorithm of ACK message 17
2.2.4建立candidate entries 的演算法 19
2.2.5 Eligible Entries的選擇 20
2.2.6 Routing Table的建立 24
2.3　Packet Forwarding Subprotocol 24
2.3.1 Anycast entry之搜尋 24
2.3.2 Anycast entry之選擇 25
2.3.3 Anycast 封包之傳送 29
第三章 模擬結果 31
3.1 實驗一 31
3.2 實驗二 33
3.3 實驗三 36
3.4 實驗四 38
3.5 實驗五 41
3.6 實驗六 43
3.7 實驗七 46
第四章 結論 48
參考文獻 49

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