Modeling and performance analysis for IPv6 traffic with multiple QoS classes

This paper focuses on the modeling and performance analysis for IM traffic with multi-class QoS in virtual private networks (VPN). The multi-class QoS is implemented on differentiated service basis using priority scheme of 4 bits defined in the packet header of IM. A VPN-enabled IP router is modeled as a tandem queuing system in which each output link consists of two paral lel priority output queues. The high-priority queue is used to carry the de lay sensitive traffic while the low-priority queue is used to carry the del ay insensitive traffic. On the other hand, multiple thresholds are implemen ted in each queue, respectively, for packet loss priority control. The perf ormance analysis is done using fluid flow techniques. The numerical results obtained from the analysis show that the differentiated service based on t he priority schemes defined in IM is able to effectively satisfy the multi- class QoS requirement for supporting multimedia services in VPN. The perfor mance trade-off between the delay sensitive traffic and delay insensitive t raffic in terms of traffic throughput, packet loss probability and end-to-e nd delay in VPN networks is presented. (C) 2001 Elsevier Science B.V. All r ights reserved.