A Performance Improvement Method with Considering of Congestion Prediction and Packet Loss on UDT Environment

UDT 환경에서 혼잡상황 예측 및 패킷손실을 고려한 성능향상 기법

  • 박종선 (전북대학교 전자정보공학부) ;
  • 이승아 (전북대학교 전자정보공학부) ;
  • 김승해 (한국과학기술정보연구원) ;
  • 조기환 (전북대학교 전자정보공학부)
  • Received : 2010.12.02
  • Accepted : 2011.01.14
  • Published : 2011.02.28


Recently, the bandwidth available to an end user has been dramatically increasing with the advancing of network technologies. This high-speed network naturally requires faster and/or stable data transmission techniques. The UDT(UDP based Data Transfer protocol) is a UDP based transport protocol, and shows more efficient throughput than TCP in the long RTT environment, with benefit of rate control for a SYN time. With a NAK event, however, it is difficult to expect an optimum performance due to the increase of fixed sendInterval and the flow control based on the previous RTT. This paper proposes a rate control method on following a NAK, by adjusting the sendInterval according to some degree of RTT period which calculated from a set of experimental results. In addition, it suggests an improved flow control method based on the TCP vegas, in order to predict the network congestion afterward. An experimental results show that the revised flow control method improves UDT's throughput about 20Mbps. With combining the rate control and flow control proposed, the UDT throughput can be improved up to 26Mbps in average.


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