TCP TS-Prio: An Approach to end-to-end service differentiation for DiffServ AF classes

Among the problems related to the Differentiated Service (DiffServ) architecture two are providing minimum bandwidth guarantee to a specific service class and the fair bandwidth sharing for the streams of the class aggregate. One elegant alternative to end-to-end service differentiation can be based on end point intelligence to control losses and delays when transferring data of individual Transmission Control Protocol streams. This paper describes a simple method to differentiate services based on congestion control parameter configuration of a TCP’s server, a priority marker, and that is still compatible to the mainly TCP implementations. A concept proof and results from simulation models are presented. We found out that our proposed approach also improves bandwidth share fairness among TCP’ individual flows of an aggregate.