Nasa tests 'interplanetary internet'

Turing award winner Vint Cerf devised Nasa's system

Nasa has successfully tested a communications system for use in space that it calls an "interplanetary internet".

The communications system was devised by Turing award winner and Google evangelist Vint Cerf, and has been in development for the past 10 years in association with Nasa scientists.

In its first test the system successfully carried data between the Earth and a satellite 20 million miles away.

"This is the first step in creating a totally new space communications capability, an interplanetary internet," said Adrian Hooke, team lead and manager of space-networking architecture, technology and standards at Nasa headquarters in Washington.

The system uses disruption-tolerant networking (DTN) to overcome the difficulties of transporting data across huge distances, which is similar to the internet's methodology in that it uses distributed nodes to pass on data.

Unlike TCP/IP, however, which assumes a constant connection at either end of the communications channel, DTN nodes store the data if the recipient cannot be reached, or pass it on to a node which can.

"There are 10 nodes on this early interplanetary network," said Scott Burleigh of Nasa's Jet Propulsion Lab (JPL), lead software engineer for the demonstrations.

"One is the Epoxi spacecraft itself and the other nine, which are on the ground at JPL, simulate Mars landers, orbiters and ground mission-operations centres."

The tests are now being rolled out to the International Space Station and will be used in future missions to co-ordinate communications between probes around other planets.