網路位址轉譯機制與行動式網際網路協定之整合

Abstract

結合無線網路與網際網路是目前通訊環境發展的一個趨勢，然而隨著眾多的無線設備加入網際網路，網際網路位址不足的問題將愈形嚴重。在網際網路之中，網路位址轉譯機制最常被用以解決網際網路位址不足問題，因此整合行動式網際網路協定與網路位址轉譯機制是結合無線網路與網際網路的一項關鍵問題。在本論文當中，我們首先分析行動式網際網路協定與網路位址轉譯機制的運作流程，並歸納出四項衝突。針對這些衝突，我們分別提出了三個解決的方法，並討論其在整合式環境中的實現方法與訊息傳遞的格式。與其他的解決方式相比，我們並非提出一個新的網際網路協定，而是整合現有的無線網路以及網路網路技術來解決問題，與目前的網路環境相容。此外，其他的網際網路上的主機不需要額外的通訊協定便可以與無線設備相互溝通。

In this thesis, we examine the issues of integrating Mobile IP with Network Address Translator (NAT), which is a popular routing mechanism to address depletion problem. With the increasing deployment of wireless Internet access devices that use Mobile IP as the network layer protocol, integrating Mobile IP with NAT has become one of the most critical missions to scale up the deployment. We first analyze the interference of NAT and Mobile IP and identify four inherent conflicts, and three schemes are proposed to reconcile the conflicts. We describe the design as well as the detail message formats of our schemes. In contrast to previous work, our solution takes advantage of adding new Mobile IP extensions rather than defining a new Mobile IP protocol, thus achieve a higher level of compatibility with previous Mobile IP implementations. Moreover, no change is required on fixed IP hosts to communicate with mobile hosts.