High-Speed TCP Variants
There have been numerous ideas for improving TCP
over the years. Some of those ideas have been adopted by mainstream operations (after thorough review). Recently there has been an uptake in work towards improving TCP's behavior with LongFatNetworks
. It has been proven that the current congestion control
algorithms limit the efficiency in network resource utilization. The various types of new TCP implementations introduce changes in defining the size of congestion window. Some of them require extra feedback from the network. Generally, all such congestion control protocols are divided as follows.
- explicit congestion control protocols (Uses explicit feedback from the router)
- implicit congestion control protocols (Relies on implicit measurements of congestion such as loss or delay)
An orthogonal technique for improving TCP's performance is automatic buffer tuning
All papers about individual TCP-improvement proposals contain comparisons against older TCP to quantify the improvement. There are several studies that compare the performance of the various new TCP variants, including
- TCP Stack Measurements on Lightly Loaded Testbeds, Les Cottrell (SLAC), 2002-2003
- Evaluation of Advanced TCP Stacks on Fast Long-Distance Production Networks, H. Bullot, R. Les Cottrell, R. Hughes-Jones, J. Grid Comput. 1(4): 345-359 (2003)
- FAST TCP in High-Speed Networks: An Experimental Study, S. Hegde, D. Lapsley, B. Wydrowski, J. Lindheim, D. Wei, C. Jin, S. Low, and Harvey Newman, GridNets 2004
- Protocols for long-distance networks, Guy Almes, TERENA Networking Conference 2004, PowerPoint presentation. This presentation walks through the problem space of transferring large amounts of data over LFNs, and briefly presents many of the TCP variants in this section, as well as some non-TCP approaches.
- Measured Comparitive Performance of TCP Stacks, S. Jansen and A. McGregor, Proc. PAM 2005
- A step toward realistic evaluation of high-speed TCP protocols, S. Ha, Y. Kim, L. Le, I. Rhee, and L. Xu, 2006
- TCP Evaluation Discussion Forum, http://www.hamilton.ie/net/eval/
- Gigabit TCP, G. Huston, The Internet Protocol Journal, Vol. 9, No. 2, June 2006. Contains useful descriptions of many modern TCP enhancements.
- Faster, G. Huston, June 2005. This article from ISP Column looks at various approaches to TCP transfers at very high rates.
- Congestion Control in the RFC Series, M. Welzl, W. Eddy, July 2006, Internet-Draft (work in progress)
- ICCRG Wiki, IRTF (Internet Research Task Force) ICCRG (Internet Congestion Control Research Group), includes bibliography on congestion control.
- RFC 6077: Open Research Issues in Internet Congestion Control, D. Papadimitriou (Ed.), M. Welzl, M. Scharf, B. Briscoe, February 2011
- PFLDnet (International Workshop on Protocols for Fast Long-Distance Networks): 2003, 2004, 2005, 2006, 2007, 2009, 2010. (The 2008 pages seem to have been removed from the Net.)
- 28 May 2005 - 03 Feb 2011
- 10 Oct 2005
- 25 Feb 2008