Five new TCP Congestion Control Algorithms Project

The FreeBSD Foundation is pleased to announce that Swinburne University's Technology's Centre for Advanced Internet Architectures has been awarded a grant to implement five new TCP congestion control algorithms in FreeBSD.

Correctly functioning congestion control (CC) is crucial to the efficient operation of the Internet and IP networks in general. CC dynamically balances a flow's throughput against the inferred impact on the network, lowering throughput to protect the network as required.

The FreeBSD operating system's TCP stack currently utilizes the defacto standard NewReno loss-based CC algorithm, which has known problems coping with many aspects of modern data networks like lossy or large bandwidth/delay paths. There is significant and ongoing work both in the research community and industry to address CC related problems, with a particular focus on TCP because of its ubiquitous deployment and use.

Swinburne University of Technology's ongoing work with FreeBSD's TCP stack and congestion control implementation has progressively matured. This project aims to refine their prototypes and integrate them into FreeBSD.

The project will conclude in January 2011.

Addendum:

The five protocols are:

• H-TCP for high bandwidth-delay product paths
• CUBIC for fast long-distance networks
• Vegas for end to end congestion avoidance
• and 2 new algorithms Hamilton Delay and CAIA-Hamilton Delay