在機會網路(Opportunistic Networks)中，連線品質總是難以預測而且時常發生連線中斷的情況。在此環境下，由於端點到端點之連線需要重新建立，資料也需要從來源端一再次地重傳，因此TCP/IP協定不太適用於此網路環境。為了解決這個問題，我們提出了一準時與非重傳之服務能力模型，準時傳送意指在一使用者預先安排的期限內傳送完成；非重傳意指從來源端傳送出去只需一次，避免一旦傳輸失敗均須自來源端重新傳輸的重複傳輸成本付出。基於此種傳輸原則下，我們設計了一包裹層(bundle layer)傳遞平台，並且重新檢視整個傳輸過程，細分成巨觀和微觀之兩檢視重點。巨觀的檢視焦點著重在端點到端點之使用者服務需求的提供，微觀的檢視焦點則要求傳送的路徑中任意相鄰兩點間的傳輸服務品質保證。我們建構於延遲容忍網路(Delay Tolerant Networks)架構下，實作此包裹層傳遞平台。最後，實驗結果驗證了所提出之包裹層傳遞平台能夠有效地在此傳輸原則下完成資料傳輸，並解決上述問題。

In Opportunistic Networks (Oppnets), the link performance is highly unpredictable and the connections are broken frequently. The TCP protocol will perform badly in Oppnets because the end-to-end connection always needs to be reconstructed and data need to be retransmitted from the original sender again through reconstructed connection. In order to solve the problem, we investigate the principles of on-time and at-one-time delivery, in which “on-time” means to transmit data to the receiver during a pre-scheduled time period and “at-one-time” means to transmit each piece of data just once. Based on the principles, we designed a Bundle layer Transmitting Platform (BTP) in Oppnets. In BTP, we separate the transmitting process into macro and micro stages. The macro stage deals with the end-to-end transmission QoS; the micro stage focuses on the transmission between adjacent nodes along the pre-constructed delivering path. We implement the proposed BTP based on the Delay Tolerant Network (DTN). Experimental results show that the designed BTP can efficiently complete the data transmission on time and at one time.

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