There’ve been satellites orbiting Earth for half a century. But getting information to and from them is still a pain. Which is why Pentagon research arm Darpa is looking to finally hook the orbiting spacecraft up with reliable broadband connections.
It’s part of a larger movement to extend terrestrial networks into space, and eventually build an “Interplanetary Internet.” In the 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 “persistent broadband ground connectivity for spacecraft in low-Earth orbit.” The idea would be to give these satellites a near-constant feed of “100 kbps or higher” two-way connectivity, with end-to-end transmission latency of less than a second.
Unlike most Darpa projects, which are meant to pay off years or decades in the future, this would be a near-term attempt. The agency wants the system “operational in the 2012 to 2013 time frame.”
Brian Weeden, a former officer with U.S. Air Force Space Command and a technical adviser with the Secure World Foundation, says Darpa’s help would be most welcome.
“The protocol that the internet uses – TCP/IP – wasn’t really designed with space in mind. For one, the delay times between nodes can be big. One way to GEO [geosynchronous orbit] is 300 milliseconds at the speed of light, there and back over half a second of built-in network lag before anything else adds to it. That’s one reason why getting internet from satellites sucks right now,” he tells Danger Room.
“If you go lower than GEO, then of course satellites are always moving and thus not always overhead. It would be a huge help to have a protocol that can automatically store and forward packets when the satellite is present or not,” 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 revolutionary construct. That you can drop a packet of data on it with only a starting and destination address and it finds its way there without any directions is pretty astonishing,” Weeden explains.
“The payloads on most satellites don’t work that way – payload operators need to configure specific transponders for specific users and applications. So part of this is trying to bring those internet concepts of automatic routing and network config to satellite constellations, and perhaps to make them extensions of the land-based internet infrastructure.”
Darpa’s deadline for ideas of how to pull it off is Nov