Insertion Based Packets Scheduling for providing QoS guarantee in switch systems

In this paper we propose the Insertion Based Packets Scheduling (IBPS), a novel packet scheduling method which can significantly reduce the maximum packet delay and delay jitter of high priority real-time data in packet switch systems. Traditional packet-by-packet scheduling will block a packet of real-time service in the packet queue until the transmission of a long non-real-time packet is finished if the real-time packet arrives after the beginning of the non-real-time packetpsilas transmission, and therefore has a bad effect on the delay and delay variation of the real-time service. While, in order to provide a better QoS for real-time services, the IBPS allows a real-time packet to be inserted into a non-real-time packet when the latter is being transmitted. IBPS can be applied with any existing packet scheduling algorithm, such as PQ (Priority Queuing) and WFQ etc. We build a prototype switch system, which can use both the IBPS based PQ and traditional packet-by-packet based PQ for packets scheduling, to evaluate the performance of IBPS. Test results of this prototype system show that IBPS based packets schedulers can achieve significantly lower maximum packet delay and delay jitter of real-time service.