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BIC-TCP 6,000 Times Quicker Than DSL
An anonymous reader writes "North Carolina researchers have developed an Internet protocol, subsequently tested and affirmed by Stanford, that hums along at speeds roughly 6,000 times that of DSL. The system, called BIC-TCP, beat out competing protocols from Caltech, University College London and others. The results were announced at IEEE's annual communications confab in Hong Kong." Update: 03/16 04:46 GMT by T : ScienceBlog suggests this alternate link while their site is down.
An awful lot of propagation delay tends to be equipment-internal rather than wire-length. Until you start talking about REALLY long distances like using satellite-based networking, anyway.
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Slowing down so here it is...
New protocol could speed Internet significantly
Posted on Monday, March 15 @ 14:04:08 EST by bjs
Researchers in North Carolina have developed a data transfer protocol for the Internet that makes today's high-speed Digital Subscriber Line (DSL) connections seem lethargic. The protocol is named BIC-TCP, which stands for Binary Increase Congestion Transmission Control Protocol. In a recent comparative study run by the Stanford Linear Accelerator Center (SLAC), BIC consistently topped the rankings in a set of experiments that determined its stability, scalability and fairness in comparison with other protocols. The study tested six other protocols developed by researchers from schools around the world, including the California Institute of Technology and the University College of London. BIC can reportedly achieve speeds roughly 6,000 times that of DSL and 150,000 times that of current modems.
From North Carolina State University:
NC State Scientists Develop Breakthrough Internet Protocol
Researchers in North Carolina State University's Department of Computer Science have developed a new data transfer protocol for the Internet that makes today's high-speed Digital Subscriber Line (DSL) connections seem lethargic.
The protocol is named BIC-TCP, which stands for Binary Increase Congestion Transmission Control Protocol. In a recent comparative study run by the Stanford Linear Accelerator Center (SLAC), BIC consistently topped the rankings in a set of experiments that determined its stability, scalability and fairness in comparison with other protocols. The study tested six other protocols developed by researchers from schools around the world, including the California Institute of Technology and the University College of London.
Dr. Injong Rhee, associate professor of computer science, said BIC can achieve speeds roughly 6,000 times that of DSL and 150,000 times that of current modems. While this might translate into music downloads in the blink of an eye, the true value of such a super-powered protocol is a real eye-opener.
Rhee and NC State colleagues Dr. Khaled Harfoush, assistant professor of computer science, and Lisong Xu, postdoctoral student, presented a paper on their findings in Hong Kong at Infocom 2004, the 23rd meeting of the Institution of Electrical and Electronics Engineers Communications Society, on Thursday, March 11.
Many national and international computing labs are now involved in large-scale scientific studies of nuclear and high-energy physics, astronomy, geology and meteorology. Typically, Rhee said, "Data are collected at a remote location and need to be shipped to labs where scientists can perform analyses and create high-performance visualizations of the data." Visualizations might include satellite images or climate models used in weather predictions. Receiving the data and sharing the results can lead to massive congestion of current networks, even on the newest wide-area high-speed networks such as ESNet (Energy Sciences Network), which was created by the U.S. Department of Energy specifically for these types of scientific collaborations.
The problem, Rhee said, is the inherent limitations of regular TCP. "TCP was originally designed in the 1980s when Internet speeds were much slower and bandwidths much smaller," he said. "Now we are trying to apply it to networks that have several orders of magnitude more available bandwidth." Essentially, we're using an eyedropper to fill a water main. BIC, on the other hand, would open the floodgate.
Along with postdoctoral student Xu, Rhee has been working on developing BIC for the past year, although Rhee said he has been researching network congestion solutions for at least a decade. The key to BIC's speed is that it uses a binary search approach - a fairly common way to search databases - that allows for rapid detection of maximum network capacities with minimal loss of information. "What takes TCP two hours to determine, BIC can do in les
To quote the part that says what the article is actually about:
What they mean is that current TCP protocol becomes a bottleneck at high bandwidth applications, so a new protocol is designed that would be efficient up to ~6000xDSL speed (just a pot-shot guess, up to 9Gb/S?). It has nothing to do with pushing data down the POTS line, just that if one day you had a fat pipe to your house, this new protocol would make use of it properly unlike today's TCP.
It's a stupid comparison, but I guess they expect people to not have an idea what 9Gb/S is...
My life in the land of the rising sun.
High-speed networks with large delays present a unique environment where TCP may have a problem utilizing the full bandwidth. Several congestion control proposals have been suggested to remedy this problem. In these protocols, mainly two properties have been considered important: TCP friendliness and bandwidth scalability. That is, a protocol should not take away too much bandwidth from TCP while fully utilizing the full bandwidth of high-speed networks. We presents another important constraint, namely, RTT (round trip time) unfairness where competing flows with different RTTs may consume vastly unfair bandwidth shares. Existing schemes have a severe RTT unfairness problem because the window increase rate gets larger as window grows - ironically the very reason that makes them more scalable. The problem occurs distinctly with drop tail routers where packet loss can be highly synchronized. Bic-TCP is a new protocol that ensures a linear RTT fairness under large windows while offering both scalability and bounded TCP-friendliness. The protocol combines two schemes called additive increase and binary search increase. When the congestion window is large, additive increase with a large increment ensures linear RTT fairness as well as good scalability. Under small congestion windows, binary search increase is designed to provide TCP friendliness.
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Speed-of-light is 186,000,000 meters per second - from (Cincinnatti) Ohio to Minneapolis is roughly 1600km by highway, which would leave you with a wire-speed delay of only 16ms round-trip.
The extra 34ms you get on a well routed network generally tends to be time spent getting passed through intermediate routers along the way. Each router *does* add a noticeable amount of delay all of its own, apart from wire delay.
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This article is much clearer. http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
I'm in Dr. Rhee's CSC316 (Data Structures for Computer Scientists) course. He absolutely knows his stuff, but he can be very hard to understand sometimes. His website is here, with a picture of the guy that doesn't really do him justice. When he walks into the classroom, I swear he looks like one of the laid-back teachers that will just let you slide by through the course, but he *really* makes you learn the material, inside and out.
Anyway, if you're interested in a link to the original article hosted off of the NCSU servers, it is here.
-bigginal
First, the actual paper is more informative. The crux of the argument is as follows.
If you have a fat pipe, say 1 to 10GB/s, standard TCP will not fully utilize the bandwidth because the congestion control algorithm throttles the rate. As packets move and there are no errors, the rate increases, but not nearly fast enough. In particular, it takes 1.5 hours of error-free data transfer to reach full capacity, and a single error will cut the connection's bandwidth in half.
BIC-TCP uses a different algorithm for congestion control that is more effective at these speeds.
End of news flash.
-Hope
You appear to be rather confused.
Modems that plug into your regular telephone line send a signal over a POTS (Plain-Old Telephone Service) phone line. This signal first goes to your telcos closest routing box, then to your telcos closest branch office. From there it gets routed to wherever your phone call was made to, etc... The technology used to route these signals is limited to a maximum THEORETICAL capacity of less than 64kbps because certain (or all) legs of the telephone network are analogue, not digital. That 'theoretical' rate is based on how much noise a typical telephone call has in it. There is simply no way to pass a denser signal through the line than that, according to our understandings of physics and math.
The only similarity that DSL has to POTS internet connections is that the physical wires to your house are compatible and that (sometimes) the two technologies can be used over a single pair of them. Once the signal of a DSL line gets to its very first junction, it has nothing in common with your phone line any longer. It gets sent to a DSLAM bank at your nearest telco site, then sent into the larger regional DSL network and then finally routed out into the internet at large.
What this means is, basically, is 1) there is a good reason why modem speeds haven't increased at all since 56kbps modems came out -- it's physically impossible for them to go faster. 2) DSL technology is transitory -- It only exists because people currently have wires from their telco already coming into their homes. I predict that slowly, over the next 10 years, we'll see telecommunications turn on its head. Instead of internet service being delivered over phone lines, we will have phone service delivered over internet connections. These lines may take the form of twisted-pair wires as is used in DSL, multiple twisted-pair wire groups as are used in ethernet, coaxial wires currently used in cable-tv/cable-modem service, or fiber-optical cables. The only thing I can guarantee is that they won't be routed through the telephone network before being passed into the internet.
DSL is a modulation technology. You can do whatever you want with the bits entering and leaving the modulator/demodulator (mo-dem). Frame Relay and ATM are the predominant "layer2" transports with PPP gaining ground (PPPoKitchenSink is all the rage) and RFC1489(?) bridged ethernet losing ground (which is a shame as it has the lowest protocol overhead of all of them, esp. PPP.)
What is BIC trying to fix? It certainly isn't "the internet" as most links, on average, run at a fraction of their available bandwidth. TCP can fill up more bandwidth than most people can aford. It looks like the researchers with these insane connections and even more insane data sets want the holy grail of zero protocol overhead and none of the inherent throttling. (TCP limits the number of packets it will transmit before pausing for an ack. As a result, a single TCP connection usually will not consume a gigE link -- 4 connections certainly can.)
It would be interesting to know how far out an implimentation of such a protocol on a large scale is.
It already IS implemented.
Or do you mean a large-scale "rollout"?
If so, why bother? Unless you have a REALLY fat pipe and need to use it all for one stream, of course. (But not many need to do that, and the ones that do can now install it on both end points.)
The phrasing of the article is leading to confusion. This is about a PROTOCOL, not about the UNDERLYING TRANSPORT.
The TCP protocol, with its windows, handshaking turnarounds, and timeouts, imposes its own limit on the speed of the data transfer through it. For decades the limit imposed by TCP was so far above the limits imposed by the data rates of the underlying transport that it wasn't a major issue.
But now some people are starting to have REALLY fast pipes. And for them TCP is becoming the limiting factor.
So now reasearchers have come up with a tweaked version of TCP that won't hit the wall until the pipe is a LOT faster than what YOU can rent from your ISP. (Unless you're renting an OC-192, in which you might be starting to fall a little short of its capacity. But if you've got OC-48 or below you're fine.)
When you CAN rent something over 6 Gbps, and you want to routinely use it all for a single TCP connection to get a REALLY FAST fast download, you might want to ask the nice professors for a THIRD generation TCP. B-)
Meanwhile, if you're on an ordianry connection you're not going to increase your data rate by a factor of 6,000 by switching protocols. You might get a little bit closer to the line rate with this SECOND generation TCP. But that's it.
Expect to see this start to gradually start showing up in protocol stacks as an option - automatically configured if both ends know about it and the inventors have come up with a backward-compatible negotiation. That way you'll be able to make better use of fat pipes when you can finally get them.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
For those that found a dead link, a better article: 'Better' TCP Invented
Researchers in North Carolina State University's Department of Computer Science have developed a new data transfer protocol for the Internet that makes today's high-speed Digital Subscriber Line (DSL) connections seem lethargic.
A speech...