인터넷 혼잡제어를 위한 안정적인 큐 관리 알고리즘

A Stabilized Queue Management Algorithm for Internet Congestion Control

  • 발행 : 2004.02.01

초록

현재의 인터넷 라우터는 Drop tail 방식으로 큐 안의 패킷을 관리한다. 따라서 네트워크 트래픽의 지수적인 증가로 인해 발생하는 혼잡 상황을 명시적으로 해결 할 수 없다. 이 문제를 해결하기 위해 IETF(Internet Engineering Task Force)에서는 RED(Random Early Detection) 알고리즘과 같은 능동적인 큐 관리(Active Queue Management)알고리즘을 제시하였다. 하지만 RED 알고리즘은 네트워크 환경에 따른 매개 변수의 설정의 어려움을 가지고 있어 잘못된 매개변수 설정으로 인하여 네트워크 성능을 저하시키는 문제를 발생시키며 전체 망에 불안정한 혼잡제어를 야기 시킬 수 있다. 본 논문에서는 기존의 큐 관리 알고리즘을 개선한 SQM(Stabilized Queue Management) 알고리즘을 제안하였다. SQM 알고리즘은 다양한 네트워크 조건에 대해 좋은 성능을 얻을 수 있도록 쉽게 매개 변수설정이 가능하며 불필요한 패킷 패기율을 줄여 효율적으로 혼잡상황을 제어한다. 제안한 알고리즘의 성능을 검증하기 위해 기존의 방법과 시뮬레이션을 이용하여 비교하였다.

In order to reduce the increasing packet loss rates caused by an exponential increase in network traffic, the IETF(Internet Engineering Task Force) is considering the deployment of active queue management techniques such as RED(Random Early Detection). But, RED configuration has been a problem since its first proposal. This problem is that proposed configuration is only good for the particular traffic conditions studied, but may have detrimental effects if used in other conditions. While active queue management in routers and gateways can potentially reduce packet loss rates in the Internet, this paper has demonstrated the inherent weakness of current techniques and shows that they are unstable for tile various traffic conditions. The inherent problem with these queue management algorithms is that they all use static parameter setting. In this paper, in order to solve this problem, a new active queue management algorithm called SQM(Stabilized Queue Management) is proposed. This paper shows that it is easy to parameterize SQM algorithm to perform well under different congestion scenarios. This algorithm can effectively reduce packet loss while maintaining high link utilizations and is good for the various traffic conditions.

키워드

참고문헌

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