UMTS多媒體廣播群播服務之檔案修復之模擬研究

Abstract

3GPP 23.246 定義了多媒體廣播群播服務（Multimedia Broadcast Multicast Service ； MBMS）標準來有效率地在通用行動通訊服務（Universal Mobile Telecommunications System ； UMTS）的核心網路中傳遞多媒體群播內容。在MBMS 服務傳輸過程中，由於網路擁塞等因素而造成資料的遺失或是使用者接收到錯誤的資料。因此，3GPP 26.346 提出了三種檔案修復方案來修復這些遺失或是錯誤的資料。然而，這些方案會對通用行動通訊服務的核心網路造成多餘的資料傳輸或是額外的信令傳遞。為了減少資料的傳輸以及解決額外信令傳遞等問題，本論文提出了新的檔案修復方案稱為Reuse Bearer Service（RBS），並且實作模擬模型來評估這些檔案修復方案之效能。我們的研究顯示，以修復所有錯誤資料所耗費之網路資源為考量時，RBS 方案優於3GPP 所定義的三種檔案修復方案。

3GPP 23.246 defines the Multimedia Broadcast and Multicast Service (MBMS) standard to efficiently deliver multimedia content over the Universal Mobile Telecommunication System (UMTS). Duration the MBMS content transmission, a UE may receive a corrupted file block (CFB) due to network congestion, etc. Therefore, 3GPP 26.346 proposes three file repair schemes to retransmit the CFBs. However, these schemes introduce extra data traffic or signaling overhead to the UMTS network. To reduce extra data traffic and signaling overhead, this thesis proposes a new file repair scheme Reuse Bearer Service (RBS), and four simulation models are conducted to investigate the performance of three 3GPP file repair schemes and RBS scheme. Our study indicates that in terms of total cost for recovering the CFBs, the RBS scheme always outperforms three 3GPP file repair schemes.