Performance Analyzing And Optimizing On BP/UDPCL Over Delay-Tolerant-Network

In deep-space communication situation, Delay Tolerant Networking(DTN) architecture is now considered to be the most suitable network architecture for overcoming deep space harsh communication environment. High error rates, long network latency, high uplink and downlink asymmetric ratio, easy interrupted communication link are several major features to have the in deep-space communication environment. “Custody Transfer” is a key mechanism of BP protocol in DTN architecture which can overcome deep-space communication network link of easy to break, then reliable transmission of data to the destination node can be guaranteed. However, little work has been done in performance analyzing of Bundle Protocol in deep-space communications.The main content of this paper is divided into two parts, first, for the high error rate characteristics in deep-space communication network, combine the function of Error Correction Code with the Bundle Protocol, and then analysis data transmission characteristic of BP. Secondly, due to the high error rate in deep space environment, large amounts of data packet retransmission always happens. In the case that can’t avoid packet retransmission, analysize how to set the RTO(Retransmit Time Out) time parameters to achieve the best transmission performance. A DTN simulation software name Interplanetary Overlay Network(ION) developed by JPL was used to simulation the BP file transmission in deep-space for the related study. Analytical models are built to characterize the file delivery performance of BP/UDPCL/UDP stack.