TCP Karak: A New TCP AIMD Algorithm Based on Duplicated Acknowledgements for MANET


Transmission Control Protocol (TCP) performance over MANET is an area of extensive research. Congestion control mechanisms are major components of TCP which affect its performance. The improvement of these mechanisms represents a big challenge especially over wireless environments. Additive Increase Multiplicative Decrease (AIMD) mechanisms control the amount of increment and decrement of the transmission rate as a response to changes in the level of contention on routers buffer space and links bandwidth. The role of an AIMD mechanism in transmitting the proper amount of data is not easy, especially over MANET. This is because MANET has a very dynamic topology and high bit error rate wireless links that cause packet loss. Such a loss could be misinterpreted as severe congestion by the transmitting TCP node. This leads to unnecessary sharp reduction in the transmission rate which could degrades TCP throughput. This paper introduces a new AIMD algorithm that takes the number of already received duplicated ACK, when a timeout takes place, into account in deciding the amount of multiplicative decrease. Specifically, it decides the point from which Slow-start mechanism should begin its recovery of the congestion window size. The new AIMD algorithm has been developed as a new TCP variant which we call TCP Karak. The aim of TCP Karak is to be more adaptive to mobile wireless networks conditions by being able to distinguish between loss due to severe congestion and that due to link breakages or bit errors. Several simulated experiments have been conducted to evaluate TCP Karak and compare its performance with TCP NewReno. Results have shown that TCP Karak is able to achieve higher throughput and goodput than TCP NewReno under various mobility speeds, traffic loads, and bit error rates.

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Almobaideen, W. and Al-maitah, N. (2014) TCP Karak: A New TCP AIMD Algorithm Based on Duplicated Acknowledgements for MANET. International Journal of Communications, Network and System Sciences, 7, 396-407. doi: 10.4236/ijcns.2014.79041.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Allman, M., Paxson, V. and Stevens, W. (1999) TCP Congestion Control. IETF RFC 2581.
[2] Lai, C., Leung, K.-C. and Li, V.O.K. (2010) Enhancing Wireless TCP: A Serialized-Timer Approach. 2010 Proceedings IEEE INFOCOM, San Diego, 14-19 March 2010, 1-5.
[3] Psaras, I., Tsaoussidis, V. and Mamatas, L. (2005) CA-RTO: A Contention-Adaptive Retransmission Timeout. 14th IEEE International Conference on Computer Communications and Networks, 32, 174-184.
[4] Henderson, T., Floyd, S., Gurtov, A. and Nishida, Y. (2012) The NewReno Modification to TCP’s Fast Recovery Algorithm, RFC 6582.
[5] Almobaideen, W., Al-Soub, R. and Sleit, A. (2013) MSDM: Maximally Spatial Disjoint Multipath Routing Protocol for MANET. Communications and Networks, 5, 316-322.
[6] Qaddoura, E., AlMobaideen, W. and Omari, A. (2006) Distributed Clusterhead Architecture for Mobile Ad Hoc Networks. Journal of Computer Science, 2, 583-588.
[7] Casetti, C., Gerla, M., Mascolo, S., Sanadidi, M.Y. and Wang, R. (2001) TCP Westwood: Bandwidth Estimation for Enhanced Transport over Wireless Links. Proceedings of ACM MOBICOM, 287-297.
[8] Qaddoura, E., Daraiseh, A., AlMobaideen, W., Muammar, R. and Al-Walaie, S. (2006) TCP Optimal Performance in Wireless Networks Applications. Journal of Computer Science, 2, 455-459.
[9] Kesselman, A. and Mansour, Y. (2003) Adaptive AIMD Congestion Control. Proceedings of the Twenty-Second Annual Symposium on Principles of Distributed Computing.
[10] Tuan Tran Thai, Changuel, N., Kerboeuf, S., Faucheux, F., Lochin, E. and Lacan, J. (2013) Q-AIMD: A Congestion Aware Video Quality Control Mechanism. 20th International Workshop on Packet Video (PV), 1, 12-13
[11] Saucez, D., Grieco, L. and Barakat, C. (2012) AIMD and CCN: Past and Novel Acronyms Working Together in the Future Internet. CSWS'12 Proceedings of the 2012 ACM Workshop on Capacity Sharing, 21-26.
[12] Sreenivas, B., Bhanu Prakash, G. and Ramakrishnan, K. (2012) An Adaptive Congestion Control Technique for Improving TCP Performance over Ad-Hoc Networks. Elixir International Journal, 44, 7391-7395.
[13] Lai, C., Leung, K.C. and Li, V.O.K. (2013) Design and Analysis of TCP AIMD in Wireless Networks. 2013 IEEE Wireless Communications and Networking Conference (WCNC), 1422-1427.
[14] Almobaideen, W., Al-Khateeb, D., Sleit, A., Qatawneh, M., Al-Khdour, R. and Abu Hafeeza, H. (2013) Improved Stability Based Partially Disjoint AOMDV. International Journal of Communications, Networks, and System Sciences, 6, 244-250.
[15] Zeng, X., Bagrodia, R. and Gerla, M. (1998) GloMoSim: A Library for Parallel Simulation of Large-Scale Wireless Networks. PADS 98 Proceedings of Twelfth Workshop on Parallel and Distributed Simulation, 154-161.

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