Research And Implementation Of Priority Virtual Output Queue Scheduling Policy In Switch

With the gradual development of science and technology,the data exchange business in the computer Internet is becoming more and more complicated,and the switching equipment in the network needs to support the function of determining the order of prioritized forwarding according to the level of the business priority.In the traditional VoQ-based switch,due to the restriction of its queue cache structure,a head blocking problem may occur when performing priority scheduling.Moreover,the scheduling policies in traditional VoQ-based switches do not differentiate the priorities of different data exchange services.No matter what kind of data service arrives,the switch carries on the fair polling,according to the first service to carry on the frame to transmit.As a result,the traditional VoQ cache organization and scheduling policies have not been able to address the need for prioritized services in some industry networks,such as avionics networks.In this paper,aiming at the requirement of the switch to differentiate the priority of data services,a priority virtual output queue scheduling strategy is designed and simulated.Firstly,the basic structure of switch and frame forwarding principle based on VoQ technology are analyzed,and the existing problems of queue buffer structure in forward frame forwarding are pointed out.Then,several existing cache scheduling strategies are analyzed in detail,which can not meet the need of prioritizing scheduling.Finally,according to the demand of prioritizing frame forwarding,based on the traditional queuing model of switchboard based on VoQ technology,a new type of queue cache organization and a new type Priority virtual output queue scheduling policy.In order to verify the new queue cache structure and the actual performance of the scheduling strategy proposed in this paper,a simulation experiment platform is used to simulate the strategy,and the test traffic model and simulation test plan are designed with reference to the real data flow in the computer network.The simulation platform verifies the scheduling strategy proposed in this paper.In this paper,we propose a scheduling strategy of priority virtual output queues in the switch and simulate it on the simulation platform,which proves the value and significance of this scheduling strategy.The scheduling strategy proposed in this paper satisfies the switch's requirement of prioritizing the forwarding of data exchange services and provides an important reference for the switch arbiter and its queue cache design.