VPN over WDM

In the context of future optical networks, providing qualityof service is one of the critical research issues. Traditionaloptical networks such as synchronous optical networks/synchronous digital hierarchy (SONET/SDH) have beenperceived as high transmission rate networks withoutproviding any QoS to different traffic flows. Recently,some attention has been given to coarse-grain QoS usingdifferentiated optical services [5], and hierarchical scheduling for two classes of traffic in [6]. Some designs for offlineVPN have been proposed in [3, 4]. However, little researchwork has considered providing online VPN on opticalnetworks. By applying the virtual private network conceptto WDM, we explore in this paper how fine-grained QoSfor dynamic VPN traffic may be provided.