한국정보통신학회논문지 (Journal of the Korea Institute of Information and Communication Engineering)

  • 제12권8호
  • /
  • Pages.1384-1390
  • /
  • 2008
  • /
  • 2234-4772(pISSN)
  • /
  • 2288-4165(eISSN)
한국정보통신학회 (The Korea Institute of Information and Commucation Engineering)
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무선 Ad-hoc 네트워크에서 TCP 성능 향상을 위한 동적 혼잡윈도우 조정 알고리즘

An Dynamic Congestion Window Tuning Algorithm for TCP Performance Improvement in Wireless Ad-hoc Network

  • 김관웅 (원광대학교 전기전자정보공학부) ;
  • 배성환 (한려대학교 멀티미디어정보통신공학과)
  • 발행 : 2008.08.30
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초록

TCP는 유선망을 위하여 설계되었기 때문에, 유선망과 다른 특성을 가진 무선망에서 서비스되는 경우 성능이 크게 저하된다. 무선 Ad-hoc네트워크에서 혼잡윈도우(congestion window)값은 TCP의 성능에 크게 영향을 준다. 네트워크 상황에 따라 적절한 크기의 혼잡 윈도우 값을 설정함으로서 TCP성능을 향상시킬 수 있다. 본 논문에서는 무선Ad-hoc 네트워크에서 TCP 성능을 향상시키는 새로운 TCP 알고리즘을 제안한다. 제안된 알고리즘은 TCP 수신측에서 최적의 윈도우 크기를 측정하고, ACK 패킷의 윈도우 필드를 사용하여 CWL(Congestion Window Limit)를 최적 값에 세팅하는 최대 혼잡윈도우 조정 기법이다. 무선 Ad-hoc네트워크의 다양한 환경에서 컴퓨터 시뮬레이션을 수행한 결과 제안된 알고리즘이 기존 TCP new reno 프로토콜보다 전송률 및 패킷 손실에서 성능을 크게 향상하였다.

The TCP protocol is originally designed for wired network, however it performs very poor in wireless network due to different nature of wireless network from wired networks. In terms of TCP performance improvement in wireless Ad-hoc network, many researches show that small congestion window size of TCP connection can improve TCP performance. We propose a new TCP algorithm to improve TCP performance in wireless Ad-hoc network. The basic idea of our approach is that TCP receiver estimates the optimum window size and then sets congestion window limit of TCP sender to an optimum value by using the advertised window field in TCP ACK packet. From extensive computer simulation, the proposed algorithm shows superior performance than traditional TCP protocols in terms of packet delivery ratio and packet loss.

키워드

참고문헌

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