No abstract

Using ns-2 simulations, this paper evaluates an Adaptive Explicit Congestion Notification (AECN) router. By receiving round-trip time (RTT) source hints from each TCP flow, AECN divides flows into flow groups based on RTT ranges. AECN uses distinct flow group drop probabilities and a mark front scheme to provide higher goodput and better fairness than Random Early Detection (RED) and Explicit Congestion Notification (ECN) routers.

In this paper, we study the TCP performance in the mobile distributed computing environment using MobilelPv4 protocol. Especially effects of TCP performance by imposing different processing overheads on the network node is investigated to see whether it is justified to ignore the node processing time in such simulation study which has been adopted by the popular Network Simulator-2(NS-2).Extensive simulation using NS-2 simulator has found that there exists a very complicated nonlinear interaction among MIPv4 mobility protocol, TCP congestion control protocol and link layer packet loss recovery etc., which is far more complicated than intuitively anticipated. The conventional perception and practice that "small node processing time can be ignored" is in question. Node processing time factor must be included in network simulation settings.