||In this thesis, we investigate the problem of scheduling and managing variable-length message transmission on single-hop passive-star coupled WDM optical networks. We study this scheduling problem when the specified WDM optical networks provide the following three types of transmission services: ordinary network transmission service, best-effort real-time transmission service, and guaranteed deterministic bounded-delay transmission service. Our main contributions lie in that 1) We have put forward a general technique, which addresses both network resource assignment issue and the message transmission sequencing issue within a single framework; 2) We have proposed a set of scheduling algorithms which can be used to schedule variable-length message transmission with or without time constraints; and 3) We have set up a systematic scheme to provide guaranteed deterministic bounded-delay service to real-time application streams composed of variable-length messages. In particular, we have proposed and investigated the following algorithms which are original ideas for scheduling and managing variable-length message transmission. The Frame Shortest Job First Serve (F-SJF) algorithm, the Frame Longest Job First Serve (F-LJF) algorithm, the Frame and Queue Shortest Job First Serve (FQ-SJF) algorithm, the Frame and Queue Longest Job First Serve (FQ-LJF) algorithm, the Multiple-message- per-Node Shortest Job First Serve (MMN-SJF) algorithm, and the Multiple-message-per-Node Longest Job First Serve (MMN-LJF) algorithm combine the message sequencing schemes with the channel assignment algorithm to efficiently schedule message tramsmissions on WDM optical networks. The Receiver-Oriented Earliest AvaiLable Time Slot (RO-EATS) algorithm takes advantage of the special properties of the specified WDM network environment to eliminate message transmission blocking and to increase utilization of the network resources. The Frame Minimum Laxity First Serve (F-MLF) algorithm and the Frame and Queue Minimum Laxity First Serve (FQ-MLF) algorithm are designed to efficiently schedule the transmission of variable-length messages with time constraints. We have proposed an admission control algorithm called Sum Subset Search (SSS) algorithm which considers multiple application streams simultaneously requesting guaranteed deterministic bounded-delay service and evaluates which of the new application streams can be accepted. We have also proposed another scheduling algorithm called Adaptive Round-Robin Earliest AvaiLabLe Time Slot (ARR-EATS) algorithm which is dedicated to scheduling the transmission of variable-length message to ensure their deterministic bounded-delay service. All of those scheduling algorithms have been evaluated by both simulation experiments and mathematical models. They have been proved to be efficient scheduling algorithms in the specified WDM optical networks and could contribute to the design of future generation multimedia WDM optical networks.