光突发交换网络中支持服务质量的一种新方案

摘要

提出了光突发交换网络支持服务质量的一种新方案.在此方案中,核心节点根据到达的数据突发的优先级别,将每一出口链路的数据信道进行分组.每一组别的数据信道数主要取决于相应优先级别的数据流量.通常情况下,属于某优先级别的数据突发会被调度在相应组别的数据信道上.在高优先级别的数据突发未能预留在其相应组别的数据信道上时,可尝试为其在低组别的数据信道上预留,甚至抢占低组别内已经被预留的信道;低优先级别的数据突发不能被预留在高组别的数据信道上.另外,也考察了抢占数据突发长度与被抢占数据突发长度之间的关系.%A new approach in optical burst switching(OBS) networks with QoS support is presented in this paper. In the approach,the data channels of an outgoing link at a core node are divided into multiple groups,with each group corresponding to a service class. The number of data channels in each group is mainly determined by data traffic. In general,a data burst(DB) can be sent on a data channel reserved by its burst head packet(BHP) only in its own group. Upon failing to reserve any bandwidth in its own group,the BHP tries to re-reserve even preempted bandwidth on a data channel in a lower-priority group. A lower-priority BHP can't reserve bandwidth on any data channel in a higher-priority group. In addition,the reasonable relation between the preempting DB length and the preempted DB length is also investigated in this paper.