Scheduling algorithms for shared fiber-delay-line optical packet switches - The single-stage case

Soung Y. Liew, Gang Hu, H. Jonathan Chao

Research output: Contribution to conferencePaperpeer-review


Optical packets may arrive at an optical switch in an uncoordinated fashion. Therefore, fiber delay lines (FDLs) are needed to buffer packets when contention occurs. There have been several optical-buffered switch architectures and FDL assignment algorithms proposed in the literature. However, most of them either have high implementation complexity, or fail to schedule departure time for delayed packets. In this paper, we study the scheduling algorithms for the single-stage shared-FDL optical packet switch. We propose two new FDL assignment algorithms: the sequential FDL assignment (SEFA) algorithm and the multi-cell FDL assignment (MUFA) algorithm. Our algorithms can make resource reservation so as to schedule departure time for packets. Owing to FDL and/or output-port conflicts, the packets that fail to be scheduled are discarded before entering the switch. We show by simulation that with these algorithms, the optical-buffered switch can achieve a loss rate of ∼10 -7 even at the load of 0.9.

Original languageEnglish (US)
Number of pages7
StatePublished - 2004
EventGLOBECOM'04 - IEEE Global Telecommunications Conference - Dallas, TX, United States
Duration: Nov 29 2004Dec 3 2004


OtherGLOBECOM'04 - IEEE Global Telecommunications Conference
Country/TerritoryUnited States
CityDallas, TX


  • All-optical network
  • Fiber delay line
  • Optical packet switching
  • Scheduling algorithm

ASJC Scopus subject areas

  • General Engineering


Dive into the research topics of 'Scheduling algorithms for shared fiber-delay-line optical packet switches - The single-stage case'. Together they form a unique fingerprint.

Cite this