Pasadena (CA) – Interplanetary Internet? Shouldn’t we figure out how to survive conveniently on other planets first before we are making plans for an Internet connection on Mars? Questions like this one may come to mind when we hear NASA talking about its deep space Internet, but there is in fact a very practical use for this technology: It could enable a much more reliable and useful communications platform for future space missions that take spacecraft millions of miles away from Earth.
NASA has different names for its new technology that was recently tested successfully for the first time Deep Space Internet, Interplanetary Internet, Disruption-Tolerant Networking (DTN), but we believe that the “deep space communications network” may be the most appropriate and obvious way to describe what this technology actually does.
The basic concept of this type of “Internet” is similar to TCP/IP in the view that data packets are sent from network node to network node. However, other than in today’s technology, NASA’s DTN does not discard data when a network node cannot find another node to send the data to. Instead, the data is stored and sent to another node when it becomes available. There may be delays, but the information is delivered to the end user eventually.
“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, manager of the DTN Experiment Operations Center at NASA’s the Jet Propulsion Laboratory (JPL). “With standardized DTN, this can all be done automatically.”
NASA said that it developed the technology about ten years ago in collaboration with Vint Cerf, co-designer of the TCP/IP protocol and a vice president at Google today. NASA believes DTN is a solution to overcome delays and disruption within an interplanetary Internet, disruptions which can be caused when a spacecraft moves behind a planet, or when solar storms and long communication delays occur. The organization said that the delay in sending or receiving data from Mars takes between three-and-a-half to 20 minutes at the speed of light.
Engineers began a month-long series of DTN demonstrations in October, NASA said Data were transmitted within NASA’s Deep Space Network in demonstrations twice a week. Engineers use NASA’s Epoxi spacecraft as a Mars data-relay orbiter. There are 10 nodes on this early “interplanetary” network. One is the Epoxi spacecraft itself and the other nine, which are on the site of the JPL, simulate Mars landers, orbiters and ground mission-operations centers. Epoxi is on a mission to encounter Comet Hartley 2 in two years.
NASA said that DTN may enable new missions involving multiple landed, mobile and orbiting spacecraft, which would be “far easier to support through the use of the Interplanetary Internet”. It could ensure reliable communications for astronauts on the surface of the moon as well.