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NANOG Meeting Presentation Abstract

Changing the IP Fairness Rule with Flow Management
Meeting: NANOG44
Date / Time: 2008-10-13 3:00pm - 3:30pm
Room: Biltmore Bowl
Presenters: Speakers:

Lawrence Roberts, Anagran

Dr. Roberts is currently Founder, Chairman and Chief Architect of Anagran Inc. Anagran is currently manufacturing flow rate management network equipment, the first major improvement in packet network technology in the 40 years since Dr. Roberts designed and managed the first packet network, the ARPANET (now the Internet). At that time, in 1967, Dr. Roberts became the Chief Scientist of ARPA taking on the task of designing, funding, and managing a radically new communications network concept (packet switching) to interconnect computers worldwide. The first for nodes of the ARPANET were installed in 1969 and by 1973 when Dr. Roberts left ARPA to become CEO of Telenet (now part of Sprint), the concept of packet switching had been well proven to the world and the ARPANET had grown to 52 computers including a packet radio subnet and a satellite extension to Europe. Dr. Roberts has BS, MS, and Ph.D. Degrees from MIT and has received numerous awards for his work, including the Secretary of Defense Meritorious Service Medal, the L.M. Ericsson prize for research in data communications, in 1992 the W. Wallace McDowell Award, in 1998 the ACM SIGCOMM Award, in 2000 the IEEE Internet Award, in 2001 the National Academy of Engineering Draper Award, in 2002 the Principe de Asturias Award, and in 2005 the NEC Computer and Communication Award.
Abstract: The Internet was designed in the era when data calls were terminal to computer with one flow each way per person, and a long history of voice calls with one flow per person. Thus it should be no surprise that TCP and the Internet equipment were designed such that when congestion occurred, the result was “equal capacity per flow”. This results from large flows losing more packets than small flows when a queue overflows, which tends to equalize the rates. It was satisfying because this made users equal.

However, today computers generate the flows and they are not restricted to one flow, they can generate thousands of flows if that would improve a data transfer. Unfortunately, it will greatly improve the capacity they can achieve, more or less linearly with the number of flows. P2P discovered this in 1999 and since then it has been able to consume the majority of the pooled capacity made available for large groups of people, both in ISP’s and at Universities. Most P2P users don’t even understand that they are using the capacity paid for or intended for many other users. But the problem is not just P2P. Now that one application has used multi-flows to gain capacity; other applications like FTP are likely to do the same, if just to gain parity. Then HTTP will send each image as multi-flow and the race is on. This will quickly destroy NAT and the problems will multiply.

However, a simple alternative exists, and that is to change the equality rule to the concept of “equal capacity for equal payment”. In many cases this will be equal capacity per user, as was intended originally. This does not differentiate based on application or the data source. It is in fact much less expensive to implement than DPI looking for P2P varieties. It only requires measuring the usage of each user and equalizing their capacity. Once implemented at the network edge, it forever fixes the fairness problem and applications can then concentrate on saving money, not maximizing capacity at the expense of others.
Files: youtubeChanging the IP Fairness Rule with Flow Management
pdfRoberts Presentation(PDF)
Sponsors: None.

Back to NANOG44 agenda.

NANOG44 Abstracts

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    Danny McPherson, Arbor Networks; Warren KumariGoogle; .
  • ISP Security
    Danny McPherson, Arbor Networks; Warren KumariGoogle; .
  • Tools
    Joel Jaeggli, Nokia;


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