IPv6 traffic with multi-class QoS in VPN

This paper focuses on the modeling and performance analysis for IPv6 traffi c with multi-class QoS in virtual private networks (VPNs). The multi-class QoS is implemented on differentiated service basis using priority scheme of 4 bits defined in the packet header of IPv6. A VPN-enabled IP router is mo deled as a tandem queuing system in which each output link consists of two parallel priority output queues. The high-priority queue is used to carry t he delay sensitive traffic while the low-priority queue is used to carry th e delay insensitive traffic. On the other hand, multiple thresholds are imp lemented in each queue, respectively, for packet loss priority control. The performance analysis is done using fluid flow techniques. The numerical re sults obtained from the analysis show that the differentiated service based on the priority schemes defined in IPv6 is able to effectively satisfy the multi-class QoS requirement for supporting multimedia services in VPN. The performance trade-off between the delay sensitive traffic and delay insens itive traffic in terms of traffic throughput, packet loss probability and e nd-to-end delay in VPN networks is presented. (C) 2001 Published by Elsevie r Science B.V.