Timeslot-Reservation Based Weighted Fair Scheduling
基于时槽预定的加权公平调度策略

EPFTS (Ethernet-oriented physical frame timeslot switching) is designed to carry the most popular data link frames,i.e.,Ethernet MAC (media access control) frames,and the transmission time for an Ethernet-oriented physical frame (EPF) is defined as a timeslot for transmission and switching the physical layer frames. To resolve the data scheduling problem in EPFTS switches,this paper proposes a new type of scheduling mechanism called TRWFS (timeslot-reservation based weighted fair scheduling) based on the characteristics of EPFTS. The principle of TRWFS is to control the request time of inputs to outputs according to the number of reserved timeslots of each traffic flow and utilize a two-phase iteration mechanism to resolve request conflicts problem. This paper also puts forward three algorithms of TRWFS to show that the implementation complexity of TRWFS is about the same as round-robin based scheduling algorithms. Further simulation results show that even under heavy load conditions,TRWFS algorithms can better guarantee reserved timeslots of each I/O pairs and get better delay and throughput performance compared with other typical algorithms.