An ECN Approach to Congestion Control Mechanisms in Mobile Ad hoc Networks

Abstract

Explicit congestion notification (ECN) mechanism capture network congestion status by using feedback based mechanism.  It determines the level of congestion more accurate than pure end-to-end schemes with an ECN-like marking scheme. The purpose of the ECN bit is to notify TCP sources of an incipient congestion and mark packets before losses occur. ECN is a binary indicator which does not reflect the congestion level and its convergence speed is relatively low due to insufficient congestion feedback. In this paper, we proposed a novel approach to handle congestion in MANETs. The same is tried to resolve by using concept of explicit congestion Notification (ECN) bits which is an extension to transmission control protocol (TCP). It allows end to end notification of network congestion without dropping packets which is done conventionally in TCP/IP networks with a bit difference of additional bit. This additional bit allows more flexibility to adjust window size to handle congestion, in comparison to a single ECN bit. Aforesaid concept is tries to simulate and performance of the same has been evaluated with appropriate environment and parameters.

Keywords: Explicit Congestion Notification (ECN), Mobile ad hoc Networks (MANET), Congestion control, Congestion window Transmission Control Protocol (TCP).