本論文中，利用 Concurrent Multipath Transfer (CMT) 和 Stream Control Transmission Protocol Partial Reliability Extension (PR-SCTP) 提出一新的傳輸協定 Partially Reliable Concurrent Multipaht Transfer (PR-CMT)，主要特色是能對所有有效路徑同時傳送，並依據資料的重要性，對應到不同的prioritized stream 傳送資料。對於Real-time 應用程式，因為資料有不同的重要性和時間限制，傳送時PR-CMT 會將較高優先權資料透過高prioritized stream 傳送。如果資料的生命週期已過，PR-CMT 並不會再傳送或重傳該資料。另一方面，減少PR-CMT 傳送端所收到SACK 無法明確得知PR-CMT 接收端是否確實有收到資料。最後利用NS2 模擬，說明PR-CMT(1)在高loss rate 環境下，資料還可以在生命週期內傳送(2)保證較高prioritized stream 先傳送(3)增加傳輸效率。

In this thesis, we propose a Partially Reliable-Concurrent Multipath Transfer (PR-CMT) that is featured with artially reliable multi-path transmission and prioritized stream transmission based on the Concurrent Multipath Transfer (CMT) and the Stream Control Transmission Protocol Partial Reliability Extension (PR-SCTP). PR-CMT is devised for real-time application data with different importances and time constraint. Data in PR-CMT are associated with lifetime. Steams in PR-CMT are associated with priorities. When the lifetime of data is expired, PR-CMT would not transmit and retransmit the lifetime expired data. Higher priority streams are transmitted before lower priority treams. Thus, the transmission of higher priority data would not be blocked by lower priority data. On the other hand, the proposed PR-CMT is able to eliminate the false acked Transmission Sequence Numbers (TSNs) problem and sender induced FORWARD TSN reordering. The simulation results show that PR-CMT (i) is more resistant to the high loss rate environment, (ii) can guarantee the ransmissions of higher priority streams, (iii) and can increase the transmission efficiency.

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