One of the important issues in the design of future generation high-speed n
etworks is the provision of real-time services to different types of traffi
c with various time constraints. In this paper we study the problem of prov
iding real-time service to hard and soft real-time messages in Wavelength-D
ivision-Multiplexing (WDM) optical networks. We propose a set of scheduling
algorithms which prioritize and manage message transmissions in single-hop
WDM passive star networks based on specific message time constraints. In p
articular, we develop time-based priority schemes for scheduling message tr
ansmissions in order to increase the real-time performance of a WDM network
topology. We formulated an analytical model and conducted extensive discre
te-event simulations to evaluate the performance of the proposed algorithms
. We compared their performances with that of the state-of-the-art WDM sche
duling algorithms which typically do not consider the time constraint of th
e transmitted messages. This study suggests that when scheduling real-time
messages in WDM networks, one has to consider not only the problem of resou
rces allocation in the network but also the problem of sequencing messages
based on their time constraints.