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Communicating Even When the Network Is Down

Posted by ryuzaki0 on from the with-science dept.

coondoggie writes to mention a NetworkWorld article covering efforts to maintain network connectivity even when the network has holes. Building off of the needs of the military, the end goal is to create a service which will route around network trouble spots and maintain connectivity for users. From the article: "Researchers at BBN Technologies, of Cambridge, Mass., have begun the second phase of a DTN project, funded by $8.7 million from the Department of Defense's Defense Advanced Research Projects Agency (DARPA). Earlier this year, the researchers simulated a 20-node DTN. With each link available just 20% of the time, the network was able to deliver 100% of the packets transmitted." The article is on five small pages, with no option to see a linkable, printable version.

4 of 115 comments (clear)

  1. Re:Wait a minute... by m94mni · · Score: 5, Informative

    "But all that breaks down when the network ruptures because of repeated disconnections and long delays. BBN has developed a network protocol and code that moves information from node to node as connections become available, and can hold information in persistent storage until a connection is available. " They are solving the case when at each point in time, there is *no* end-to-end path. ARPANET assumes there is at least one path, though the path can vary over time.

  2. Re:I can get to a printable version... by Anonymous+Crowhead · · Score: 4, Informative

    link

  3. Re:What, AGAIN? by xyzzy · · Score: 4, Informative

    This is an old wive's tale that deserves to die. The ARPANet was NOT built as an experiment in resiliant networking; it was built by DARPA to connect scientists so they could share all the large computers that DARPA was funding.

    See: Where Wizards Stay Up Late
    http://www.amazon.com/Where-Wizards-Stay-Late-Inte rnet/dp/0684832674

    and
    http://www.businessweek.com/1996/38/b349359.htm

  4. No, that was packet switching by Capt.+Skinny · · Score: 4, Informative
    Wasn't that the point of the original ARPANET? To route around broken parts of the network?
    ARPANET was never about sustaining communication in the event of network failure. That goal belongs to the development of packet switching - a separate government funded project by the RAND corporation at about the same time. Sorry, I'm too lazy to dig through my e-mail to find my references.