Journal of the Institute of Electronics Engineers of Korea TC (대한전자공학회논문지TC)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Blocking probability improvement for Lightpath Setup based on GMPLS

GMPLS망 기반의 광 경로 설정을 위한 블로킹율 개선 방안

  • Im Song-Bin (Department of Electronic and Communication Engineering, Kwangwoon University) ;
  • Kim Kyoung-Mok (Department of Electronic and Communication Engineering, Kwangwoon University) ;
  • Oh Young-Hwan (Department of Electronic and Communication Engineering, Kwangwoon University)
  • 임송빈 (광운대학교 전자통신공학과) ;
  • 김경목 (광운대학교 전자통신공학과) ;
  • 오영환 (광운대학교 전자통신공학과)
  • Published : 2004.12.01
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Abstract

Increase of internet users and new types of applied traffics, have led to demand for more bandwidth for each application. Hence, the amount of internet traffic has risen sharply and it has demanded to use limited resources, such as wavelength and bandwidth, more effectively. These kind of needs can be satisfied with OXC(Optical cross-connects) based on GMPLS that carry out IP packet switching and wavelength switching at the same time and Provide very wide bandwidth. In RSVP-TE signaling of GMPLS studied by IETF. every lambda router in core network should be able to convert wavelength. So, lots of wavelength converters and needed and building and managing cost is high. Another problem is that optimized traffic is limited. In this paper We suggest strengthened GMPLS RSVP-TE signaling algorithm for a better lightpath setup. When setup signaling is blocked suggested algorithm does not send PathErr message to Edge Router, but looks for nearest lambda router which can convert wavelength and carry out setup signaling from that node. Such algorithm can reduce the chance of blocked lightpath setup signaling and provide effective arrangement of lambda router in core network by calculating proper number of wavelength converter.

최근 인터넷 사용자 수의 증가와 새로운 서비스의 등장으로 각 응용의 요구 대역폭이 증가하였다. 따라서 Internet 트래픽은 폭주하게 되었고, 고속의 백본(backbone) 네트워크가 필요하게 되었다. 이러한 요구는 IP packet switching과 wavelength switching 모두를 동시에 수행하면서 대용량의 대역폭을 지원할 수 있는 GMPLS(Generalized Multi-protocol Label Switching) 기반의 OXC(Optical cross-connects)에 의해 만족될 수 있다. 이러한 요구를 위해서는 Core망에 많은 수의 파장 변환기가 필요하고, 구축 및 운용비용(cost-effective)이 효율적일 뿐만 아니라 최적의 트래픽 전송제한을 받는 문제점을 갖고 있다. 따라서 본 논문에서는 GMPLS망에서 개선된 Lightpath setup을 위한 GMPLS의 RSVP-TE 시그널링을 제안하였다. 제안한 알고리즘은 setup 시그널링이 블로킹 되었을 때, edge router까지 PathErr 메시지를 전송하는 것이 아니라 파장 변환을 수행할 수 있는 최단거리에 위치한 람다 라우터를 찾고, 그 노드로부터 setup 시그널링을 다시 수행한다. 본 알고리즘은 Lightpath setup 시그널링의 블로킹 확률을 줄일 수 있으며, 적절한 파장 변환기 수를 산출하여 core망에서 람다 라우터의 효율적인 배치도 구현할 수 있을 것으로 사료된다.

Keywords

References

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