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Replacing TCP?
olau writes "TCP, the transfer protocol that most of the Internet is using, is getting old. These guys have invented an alternative that combines UDP with rateless erasure codes, which means that packets do not have to be resent. Cool stuff! It also has applications for peer-to-peer networks (e.g. for something like BitTorrent). They are even preparing RFCs! The guy who started it, Petar Maymounkov, is of Kademlia fame."
better replacement of TCP. TCP's legacy design carries a number of inefficiencies, the most prominent of which is its inability to utilize most modern links' bandwidth. This problem stems from the fact that TCP calculates the congestion of the channel based on its round-trip time. The round-trim time, however, reflects not only the congestion level, but also the physical length of the connection. This is precisely why TCP is inherently unable to reach optimal speeds on long high-bandwidth connections.
A secondary, but just as impairing, property of TCP is its inability to tolerate even small amounts (1% - 3%) of packet loss. This additionally forces TCP to work at safe and relatively low transmission speeds with under 1% loss rates. Nevertheless, our extended real-life measurements show that highest throughput is generally achieved at speeds with anywhere between 3% and 5% loss.
The Solution
By using our core coding technology we were able to design a reliable Internet transmission protocol which can circumvent both of the fore-mentioned deficiencies of TCP, while still remaining TCP-friendly. By using encoded, rather than plain, transmission we are able to send at speeds with any packet loss level. Rateless coding is used in conjunction with our Universal Congestion Control algorithm, which allows Rateless Internet to remain friendly to TCP and other congestion-aware protocols.
Universal Congestion Control is an algorithm for transmission speed control. It is based on a simple and clean idea. Speed is varied in a wave-like fashion. The top of the wave achieves near-optimal throughput, while the bottom is low enough to let coexisting protocols like TCP smoothly receive a fair share of bandwidth. The time lengths of the peaks and troughs can be adjusted parametrically to achieve customized levels of fairness between Rateless Internet and TCP.
The Rateless Internet transport is now available through our Rateless Socket product in the form of a C/C++ socket library. Rateless Internet is ideal for Internet-based applications, running on the network edges, that require high bandwidth in a heterogenous environment. It was specifically built with peer-to-peer and live multimedia content delivery applications in mind.
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> Coral is a nice idea with a flawed implementation. Care to explain this flamebait or shall we just leave it at that? :)
Does it support the evil bit?
Life today. Uncertainty tomorrow.