The Hong Kong University of Science and Technology
Department of Computer Science


PhD Qualifying examination


"Survey on Blocking Performance in WDM Networks with and without
Wavelength Converters"

By Mr. Xiaowen Chu



Abstract:

Wavelength division multiplexing (WDM) is a promising technology in
the future all-optical networks. This survey deals with the on-line
routing and wavelength assignment problem in dynamically re-configurable
wavelength-routed networks with and without wavelength converters. The
system is more likely to work in circuit-switched model, which means
that a sequence of end-to-end call requests for lightpath establishment
and release arrives over a period of time. The central problem is how
to select a route for each request and properly assign wavelength(s) for
the requests. The objective is to minimize the blocking probability.
This survey provides a review of some analytical models that can be
used to evaluate the blocking performance of wavelength-routed networks.
Wavelength conversion plays an important role in wavelength-routed
network because it can improve the blocking performance. However,
wavelength converters are expected to be very expensive devices.
Therefore it is important to quantify what benefits wavelength conversion
can offer. We next investigate the problem of wavelength converter
placement, which still needs to be carefully examined. Following that,
we introduce and compare some heuristic approaches of on-line routing
and wavelength assignment algorithms.


Date:			4 April 2001 (Wednesday)                 
	
Time:   		10:00 a.m. onwards		               
        
Venue:                  Room 1402 
			(Lift 25-26)
			                      
Chairman:               Dr. Rudolf Fleischer

Committee Members:      Dr. Bo Li (Supervisor)
                        Dr. Mounir Hamdi
                        Dr. Brahim Bensaou
			Prof. Xiren Cao (EE)
			


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