Implementing an IPv6 QoS management scheme using flow label & class of service fields

The core of any quality of service (QoS) scheme is how to monitor and manage traffic flows that have guaranteed QoS. The two QoS approaches used in the literature are, IntServ (integrated service) (White, P.P., 1997) and DiffServ (differentiated service) (Blake, S. et al., 1998). IntServ uses the resource reservation protocol (RSVP) for signaling the path. Decisions on QoS requests are taken by each router independently. DiffServ uses bandwidth brokers as a QoS management model to negotiate requests, communicate with edge nodes and track reservations. We propose an IPv6 QoS management scheme that uses the flow label and traffic class (TC) fields for reserving resources. Edge nodes use these two fields for classification, scheduling and monitoring traffic flows which have requested QoS from the network. Classification is not limited to a number of predefined classes, but on the priority levels (TC field). Processing time is minimized and routing is optimized as routers have to check only the flow identification fields, source IP address and flow label, to direct traffic appropriately. The QoS parameters used are end-to-end delay and packet loss. The simulations are performed on a network simulator (NS-2) (http://www.isi.edu/nsnam/ns/, 2003).