SAN FRANCISCO — With careful planning and standard communications protocols, spacecraft that have completed their primary missions could form the nodes of an interplanetary network designed to send messages across vast distances in space, Internet pioneer Vint Cerf told representatives from government, industry and academia attending NASA’s first information technology summit.

Cerf, who serves as Google Inc.’s chief Internet evangelist, began working with NASA’s Jet Propulsion Laboratory in Pasadena, Calif., more than a decade ago to develop software protocols designed to operate in spite of the lengthy delays experienced when computers on Earth or planetary outposts try to communicate with spacecraft orbiting distant planets or travelling behind the sun. That software, known as Disruption Tolerant Networking (DTN) or Bundle Protocol, is currently being implemented on the international space station and on NASA’s Epoxi spacecraft which is on a mission to rendezvous with the comet Hartley 2 later this year.

“We hope [DTN] will be put onboard the Internet Router in Space,” Cerf said. “The Cisco router that is on [Intelsat’s] Intelsat 14 has an auxiliary processor. Cisco and NASA have been working together to try to get the Bundle Protocol onboard Intelsat 14,” Cerf said Aug. 17.

Unlike the Internet Protocol, which requires an unobstructed pathway from a message’s sender to its recipient, DTN relies on a series of nodes or relay stations to transmit data. Each relay station can transmit the message to the intended recipient or to another relay station along the way.

If those DTN protocols are standardized by the Consultative Committee for Space Data Systems, they could be adopted by all spacefaring nations, Cerf said. The use of those protocols worldwide would “render spacecraft essentially interoperable, if they choose to communicate with each other,” Cerf said. “That will allow us to accrete an interplanetary backbone over the course of many decades. As these missions are launched for scientific reasons and then complete their primary mission, they will become part of the interplanetary backbone.”