Delay Resistant Transport Protocol for Deep munication.pdf.pdf

Int. J. Communications, Network and System Sciences, 2011, 4, 122-132 doi:.42015 Published Online February 2011 (rnal/s) Copyright ? 2011 SciRes. SDelay Resistant Transport Protocol for Deep munication Mohanchur Sarkar1, Kaushal K. Shukla2, Kankar S. and Navigation Applications Area, Space Applications Centre (ISRO), Ahmedabad, India 2Department puter Engineering, Institute of Technology, Banaras Hindu University, Varanasi, India E-mail: mohanchur@,{msarkar, ksd}***@, kkshukla.******@itbhu Received November 30, 2010; revised January 12, 2011; accepted January 14, 2011Abstract The throughput of conventional transport protocols suffers significant degradation with the increased Round Trip Time (RTT) typically seen in deep munication. This paper proposes a Delay Resistant Transport Protocol (DR-TCP) for point-to-munication in deep space exploration missions. The is-sues related to deep munication protocol design and the areas where modifications are necessary are investigated, and a protocol is designed that can provide good throughput to the applications using a deep space link. The proposed protocol uses a cross layer based approach to find the allocated bandwidth and avoids initial bandwidth estimation. A novel timeout algorithm estimates the timeout duration with an objec-tive to maximize throughput and avoid spurious timeout events. The protocol is evaluated through extensive simulations in ns2 considering high RTT values typically seen in Lunar and Mars works un-der different conditions of packet error rates. DR-TCP provides a significant increase in the throughput pared to traditional transport protocols under the same conditions. A novel adaptive redundant retrans-mission algorithm is also presented to take care of the high PER in deep space links. The effect of the Re-transmission Frequency has been critically analyzed considering both Lunar and Deep Sp