同步軌道通訊衛星IP網路系統規劃及IP網路通訊效能模擬研究

Abstract

商業性多媒體資訊服務的需求在現代人們的日常生活上有與日俱增的趨勢，特別是在一些聲音與影像的應用方面。而同步軌道通訊衛星由於具有廣域的通訊覆蓋區域以及與地表的相對位置變化不大的特性，在提供廣域通訊服務的應用上，便有相當的市場潛力。在普遍的應用上，衛星可以在高空上做大區域的影音廣播，或是提供跨國際的衛星電話服務。除此之外，衛星與已經蓬勃發展之不同型態的地面網路結合，也成為一種衛星網路架構的趨勢。在這種整合型的大網路裡，衛星所提供的無線傳輸通道，便扮演著其中的骨幹網路，提供長距離的訊息傳遞能力。然而，為了要與蓬勃發展的地面網路結合，衛星骨幹網路面臨了一些挑戰。由於地面網路要屬網際網路 ( Internet ) 為最大的網路型態，在網際網路上的應用與資源非常豐富，許多其他型態的網路在實際部署的時候，都有提供與網際網路結合的功能，這是為了使用來自網際網路的資訊資源所必須提供的整合能力，因此，衛星骨幹網路在設計時，也必須考慮與網際網路有相容與結合的能力。在網際網路上所使用的通訊協定 (Internet Protocol, IP)，便是我們在這個專案裡所要研究探討的部分。我們將利用網路模擬技術，評估網際網路通訊協定在衛星骨幹網路上的適用性，改良不適用於衛星骨幹網路的網際網路通訊協定以及網路系統設計，並進而提出適用於衛星骨幹網路的新網路通訊協定以及新的網路系統設計。

The demands for commercial multimedia information services are increasingly growing in our daily lives, especially those for audio and video applications. In terms of provision of wide area multimedia information services, geostationary earth orbit (GEO) satellites have a high potential because of their wide area communication coverage and geostationary characteristics. The common applications of satellites are multimedia broadcast from space and international satellite telephones. In addition, there is a trend towards integration of satellites and highly-developed terrestrial networks into a new type of infrastructure of satellite networks. In the new integrated networks, the transmission paths provided by satellites form the satellite backbone network which supports the capability of long distance transmission. In order to, however, integrate the satellite backbone network with those highly-developed terrestrial networks, some technical challenges arises. Because the Internet is dominant among terrestrial networks and is full of many kinds of information resources, many terrestrial networks are considered to integrate with the Internet when they are practically deployed. Therefore, when the satellite backbone network is designed, the capabilities of integration and compatibility with the Internet must be considered. In this project, we focus on the general communication protocol used on the Internet, called Internet protocol (IP). We will use the network simulation approach to evaluate whether the Internet protocol is suitable for satellite backbone networks, and then try to improve or modify the unsuitable parts of the Internet protocol. Furthermore, we will try to develop some new protocols or network architectures that are more suitable for IP-based satellite backbone networks.