BACKGROUND:  TCP is one of the core protocols of the Internet protocol suite, and TCP congestion control is one of the most important TCP related requests for comments (RFCs) in recent years. Fairness is an important criterion in congestion control such that two flows competing on the same narrow link node but with different propagation delays should achieve the fair share, but this does not happen with the TCP scheme currently deployed on the Internet. Previous TCP congestion control schemes include FAST TCP, which is round-trip-time fair and scalable, but lacks in friendliness to legacy TCP making it unusable realistically; TCP Hybla which has been successfully deployed on satellite networks but proves to be too aggressive and hence unstable when deployed on the internet; and BIC TCP which improves the fairness of some high-speed schemes, but is not as good as the fairness provided by legacy TCP. Regarding wireless networks, standard cell phones do not have a fast transport layer protocol installed, but rather rely on the old TCP Tahoe implementation at the client side, resulting in a lack of speed in 3G and beyond networks. TCP Libra as a fast transport layer protocol is a solution to improving the speed of cell phone networks.

INNOVATION:  The invention introduces a new way to increase and decrease the TCP congestion window. The innovation enables the most important properties of the protocol, which are fairness (in the sense of minimum delay fairness), scalability, and friendliness to legacy TCP schemes (i.e. the schemes that are currently used on the internet).

POTENTIAL APPLICATIONS 

• TCP Libra has applications in cell phone networks (round trip time fairness and higher speeds) and high speed networks (scalability and friendliness).

ADVANTAGES:

TCP Libra introduces, all at once, the following advantages:

• Round trip time fairness
• Scalability in terms of bandwidth
• And friendliness to legacy TCP

DEVELOPMENT-TO-DATE:  The invention has been developed and thoroughly tested in simulation. An implementation is available.

Reference: UCLA Case No. 2007-141