Performance of TCP over Differentiated Services Networks withATM Switching Systems

This paper determines the performance ofTCP when it is employed over Differentiated ServicesNetwork where ATM switches are used as Label SwitchingRouters, as in Request for Comments 3035.A packet discard scheme is also evaluated with the goalto classify incoming data flows in different levels of qualityof service. In particular, the assured forwarding in theDifferentiated Services per-hop-behavior, as reported inthe Request for Comments 2597, is considered as referencescenario.Different degrees of quality of service imply differentportions of bandwidth and levels of packet loss for dataflows which share the same output link. TCP performanceis investigated for Low Drop Precedence flows, orhigh priority flows, when the considered packet discardscheme is employed during congestion intervals. Numericalresults are reported and discussed for different levelsof congestion