光网络中视频业务传输的节点排队机制

对服务质量(QoS)中的队列机制进行了重点的分析, 并对先进先出(FIFO)以及具有优先级(PQ)的两种队列机制的特点进行了详细的比较。具有优先级(PQ)队列可以降低高优先级业务的平均排队时延, 但却无法保证时延抖动的要求。提出了基于具有优先级队列机制的改进方案。仿真结果表明, 新的排队机制有效得解决了具有优先级(PQ)排队机制中无法保证高优先级(视频)业务传输中的时延抖动问题, 当初始时延分布差别很大的数据包在经过节点排队调度之后, 时延抖动有了明显改善。

Node Queueing Mechanism of Video Transmission in Optical Networks

The queueing management strategy of quality of service(QoS) was analyzed as a key point. First, the performances of first in first out (FIFO) queueing mechanism and priority queuing (PQ) mechanism were obtained and compared. It was found that PQ mechanism could reduce the average delay of the higher priority traffic, but the time jitter was still not under control. Therefore, an improved algorithm based on PQ mechanism was developed to solve this problem. The simulation results showed that the delay jitter was decreased significantly by the improved algorithm, and the delay jitter was improved when the data packets of different initial time delay were queued in the nodes.