在傳統的移動通訊網路中，無線連結的頻寬太小而且無線連接與有線連接的頻寬差異太大。以致於限制了移動通訊網路在多媒體傳輸及其他需高頻寬傳送的應用，且網路頻寬不足的問題往往發生在無線連結的部分。但是新一代的移動通訊網路即第三代移動通訊系統將會改變這個情形。因為第三代系統快速的提升無線傳輸速度(最快可達2Mbps)而且提供更好的傳輸品質，所以傳送多媒體及其他需高頻寬的服務都將可以在移動通訊網路中達成。第三代系統可以提供許多以往無法提供的新服務，而這些新服務通常需支援點對多點的傳輸。在這篇論文中，我們將討論支援這些新服務將會遭遇到的問題，然後提出一個新的群播架構來克服這些問題。

In the traditional mobile communication networks, the bandwidth of wireless links is too small and the bandwidth difference between wireless links and wireline links is too large. This leads to limiting the application of mobile communication networks to transmit multimedia data and other high-bit rate services, and the problem of lacking bandwidth often occurs to wireless links. But the new generation mobile communication networks, called the third generation mobile communication systems (3G systems), will change this condition. Because the 3G systems will quickly enhance the transmission rate of the wireless links (up to 2Mbps) and provide better quality of transmission, the transmission of multimedia data and other high-bit rate services in the mobile communication networks can be achieved. The 3G systems can support many new services that are never supported before, and these new services always need support the point-to-multipoint transmission. In this thesis, we will discuss the problems of supporting these new services, and then we propose new multimedia multicasting architecture to overcome these problems.

1•Introduction…………………………………………………………………………… 1
2•Background……………………………………………………………………………… 5
2.1•The third generation mobile communication systems …………………… 5
2.1.1•Basic Specifications of 3G Systems in IMT-2000 ………………… 6
2.1.2•The Main Systems in IMT-2000 ………………………………………… 10
2.2•Multicast Routing Protocol …………………………………………………… 11
2.2.1•Source-based Tee Multicasting………………………………………… 12
2.2.2•Core-based Tee Multicasting…………………………………………… 13
2.3•Virtual Source and Virtual Destination Structure………………………… 14
2.4•Multicast Transmission Schemes………………………………………… 16
2.4.1•Replicated Adaptive Streams Scheme ……………………………… 17
2.4.2•Receiver-driven Layered Multicast Protocol………………………… 17
3•New Multicast Architecture…………………………………………………… 21
3.1•Basic Structure and Operations of the Base Station……………………… 26
3.2•Three Procedures in the Base Station …………………………………… 28
3.2.1•Join-Group Procedure ……………………………………………… 28
3.2.2•Leave-Group Procedure……………………………………………… 30
3.2.3•The Soft Hand-off Procedure………………………………………… 31
3.3•Modification to Support General Data Services ………………………… 34
3.3.1•The Modified RLM Protocol……………………………………………… 34
3.3.2•The Modified Join-Group Procedure…………………………………… 35
4•Simulations and analysis…………………………………………………………… 37
4.1•Two Analysis Indicators : DLR and TLR…………………………………… 37
4.1.1•Delay Variation to Network Loading Ratio ………………………… 37
4.1.2•Throughput to Network Loading Ratio………………………………… 38
4.2•Basic Simulation Setting …………………………………………………… 39
4.3•Simulation Results and Analysis …………………………………………… 42
4.3.1•Simulation 1 ……………………………………………………………… 42
4.3.2•Simulation 2 ……………………………………………………………… 47
4.3.3•Simulation 3 ……………………………………………………………… 51
5•Conclusions…………………………………………………………………………… 56
Reference ………………………………………………………………………………… 57
Appendix : Detail Simulation Results ……………………………………………… 59

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