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http://www.wired.com/dangerroom/2009/10/darpa-looks-to-send-the-internet-into-orbit/Darpa Looks to Send the Internet Into Orbit * By Noah Shachtman Email Author * October 27, 2009 | * 11:34 am | * Categories: DarpaWatchThere’ve been satellites orbiting Earth for half a century. But gettinginformation to and from them is still a pain. Which is why Pentagon researcharm Darpa is looking to finally hook the orbiting spacecraft up with reliablebroadband connections. It’s part of a larger movement to extend terrestrialnetworks into space, and eventually build an “Interplanetary Internet.” Inthe meantime, we might even get less-than-crappy satellite internet service —if the project works out, of course.Darpa recently issued a request for information about supplying “persistentbroadband ground connectivity for spacecraft in low-Earth orbit.” The ideawould be to give these satellites a near-constant feed of “100 kbps orhigher” two-way connectivity, with end-to-end transmission latency of lessthan a second. Unlike most Darpa projects, which are meant to pay off yearsor decades in the future, this would be a near-term attempt. The agency wantsthe system “operational in the 2012 to 2013 time frame.”Brian Weeden, a former officer with U.S. Air Force Space Command and atechnical adviser with the Secure World Foundation, says Darpa’s help wouldbe most welcome.“The protocol that the internet uses — TCP/IP — wasn’t really designed withspace in mind. For one, the delay times between nodes can be big. One way toGEO [geosynchronous orbit] is 300 milliseconds at the speed of light, thereand back over half a second of built-in network lag before anything else addsto it. That’s one reason why getting internet from satellites sucks rightnow,” he tells Danger Room.“If you go lower than GEO, then of course satellites are always moving andthus not always overhead. It would be a huge help to have a protocol that canautomatically store and forward packets when the satellite is present ornot,” Weeden adds.For years, Darpa — which backed much of the early research into the internet— has been working with other networking godfathers to put together an“interplanetary internet.”“We’re pretty used to it but the internet is actually a pretty revolutionaryconstruct. That you can drop a packet of data on it with only a starting anddestination address and it finds its way there without any directions ispretty astonishing,” Weeden explains. “The payloads on most satellites don’twork that way — payload operators need to configure specific transponders forspecific users and applications. So part of this is trying to bring thoseinternet concepts of automatic routing and network config to satelliteconstellations, and perhaps to make them extensions of the land-basedinternet infrastructure.”Darpa’s deadline for ideas of how to pull it off is Nov. 5.--The war on privilege will never end. Its next great campaign will be against the privileges of the underprivileged. H. L. Mencken
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