Dynamic Congestion Control Mechanism in Mobile Adhoc Network: TCP Westwood-DCC
Sejal Haveliwala1, Dhaval Vyas2, Hemal Shah3
1Sejal Haveliwala *, M.Sc.IT Department, Shree M. M. Patel Institute of Sciences and Research, Gandhinagar, India.
2Dr. Dhaval Vyas, Master of Philosophy, C. U. Shah University, Wadhwan, India.
3Dr. Hemal Shah, ICT Department, Ganpat University, Mehsana, India. 

Manuscript received on January 05, 2020. | Revised Manuscript received on January 25, 2020. | Manuscript published on January 30, 2020. | PP: 4784-4789 | Volume-8 Issue-5, January 2020. | Retrieval Number: E6828018520/2020©BEIESP | DOI: 10.35940/ijrte.E6828.018520

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© The Authors. Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC-BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Abstract: Transmission control protocol faces a problem of packet loss differentiation in the wireless and mobile adhoc network. Congestion control is not properly done here. It cannot manage the congestion window as per type of loss and it reduces Congestion window unnecessarily and that degrades the performance. TCP Westwood cannot identify congestion or link failure loss, and it cannot manage the congestion window as per available bandwidth. This paper discusses that TCP Westwood performs bandwidth estimation, setting up a congestion window and a slow start threshold. In mobile adhoc network, link failure may happen frequently, and it should be handled properly. Link failure can be detected with the help of retransmission timeout. Once timeout occurs Westwood performs congestion avoidance. Proposed Westwood manages three states of congestion 1) Avoidance 2) congestion and 3) No congestion, it updates congestion window and slow start threshold as per the status of network. It maintains congestion window dynamically. Network status is identified by estimated bandwidth and proportionality ratio. Proposed method is tested on NS2.35 and compared with the existing TCP variants. The proposed Westwood performs optimized link utilization and congestion control mechanism. Hence it gives significant performance for loss recovery.
Keywords: BWP (Bandwidth Proportionality Ratio, Congestion Window(Cwnd), Estimated Round Trip Time (ERTT), Last RTT Round Trip Time (RTT), Ssthresh (Slow Start Threshold), Estimated Bandwidth(BWE).
Scope of the Article: Time and knowledge Management Tools.