Abstract
Node(s)/link(s) of a network are subjected to overloading; network performance deteriorates substantially due to network congestion. Network congestion can be mitigated with the help of Explicit Congestion notification (ECN) technique. ECN notification is carried out by setting ECN bit in the TCP header. This allows for end-to-end notification of network congestion without dropping packets. ECN bit notifies TCP sources of incipient congestion before losses occur. ECN is a binary indicator (1 bit) which does not reflect the congestion level completely and so its convergence speed is relatively low. In our work, we have used an extra ECN bit (2 bit ECN). The extra bit allows for passing of additional congestion feedback to the source node. This enables the source node to determine the level of congestion based on which steps can be taken to ensure faster convergence. In comparison to single bit ECN, the additional information afforded by double bit ECN allows for more flexibility to adjust window size, to handle congestion. Simulation results have shown that the proposed method improves overall performance of the network by over 12%.
Highlights
Mobile Ad hoc Network (MANET) is a distributed system of self-organizing and independent nodes
Self re-organization and self-operation requires adapting to variations in topology and bandwidth requirements, which is the main challenge in the design of MANET
We propose an enhanced version of explicit congestion notification (ECN) scheme allows more flexible handling of congestion
Summary
Mobile Ad hoc Network (MANET) is a distributed system of self-organizing and independent nodes. In TCP (Transport Control Protocol) numbers of variants have been proposed for congestion control They can be classified into two categories according to the mechanisms used to obtain congestion feedback: explicit network feedback based schemes and pure end-to-end schemes. Explicit network feedback based schemes usually perform better than pure end-to-end ones, but many of them require modifying IP header to carry additional feedback information. This incurs complicated computation in routers and makes them unpractical in real networks. We propose an enhanced version of ECN scheme allows more flexible handling of congestion This scheme is based on the network load factor l which can be estimated very at each router and is associated with following illustrated ECN bits in the IP header for feedback.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
