A distributed call admission for a measurement-based traffic engineering in Diff-Serv architecture

Diff-Serv architecture, as proposed by IETF for supporting quality of service (QoS) in the Internet, is scalable and well suited for backbone networks, but it does not exploit resources as needed. Traffic engineering (TE) is a solution to this problem. The goal of this work is to develop a traffic engineering mechanism on Diff-Serv architecture to provide strict quality guarantees through the use of a distributed call admission (CA) algorithm, performed by each border router of the network. The overall performance with two kinds of update mechanisms in order to propagate information about network resources utilization, based on fixed time intervals and on utilization thresholds is studied. Such mechanisms with two different local admission criteria are employed. Moreover, the impact of the update packets processing delay and relaxation of the resource availability control constraint is inquired. Collected results show that the proposed TE architecture is able to achieve strict QoS guarantees and high exploitation of network resources. Furthermore, time intervals update mechanism is robust and offers linear performance gains with decreasing of the update period.