The network would help astronauts returning to the Moon.
The net has taken a giant leap that has extended cyberspace into outer space.
Nasa has successfully transmitted images to and from a spacecraft 20 million miles away with a communications system based on the net.
The Disruption-Tolerant Networking (DTN) technology is designed to work across vast distances where response times can be measured in days.
Further tests of DTN are due to take place on the International Space Station (ISS) in 2009.
"This is the first step in creating a totally new space communications capability, an interplanetary Internet," said Adrian Hooke, manager of space-networking architecture, at Nasa HQ in Washington.
The pioneering work on the DTN was done a decade ago by Vint Cerf - one of the creators of the net's basic communications protocols.
That work led to the creation of DTN which is extremely tolerant of the delays and disruptions that are likely to occur when data is shuttling between planets, satellites, space stations and distant spacecraft.
To cope with these delays - which can be brought about by solar storms or when craft are behind a planet - each node in a DTN network holds on to data sent to it until it can safely contact another node.
Using this "store and forward" mechanism ensures data is not lost and gradually works its way towards its destination.
Nasa's month-long test of DTN involved using the Epoxi spacecraft as a data-relay. Epoxi is scheduled to rendezvous with comet Hartley 2 in 2010 but was used as a test-bed while in flight.
Epoxi was used to communicate with nine other nodes based at Nasa's JPL labs on Earth, which simulated the responses of landing craft, orbiters and mission control centres.
"In space today, an operations team must manually schedule each link and generate all the commands to specify which data to send, when to send it, and where to send it," said Leigh Torgerson, DTN manager at JPL in a statement.
He added: "With standardised DTN, this can all be done automatically."
DTN will also help Nasa mount very complex missions that involve many different types of craft that before now have been hard to co-ordinate. It would also underpin communications with astronauts should a return trip to the moon take place.