Many systems are built on the hope of a steady connection. Where interruptions are common, a different approach may be needed.

NASA has successfully tested the first deep space communications network modeled on the Internet. To accomplish this, engineers from NASA's Jet Propulsion Laboratory in Pasadena, Calif., used software called Disruption-Tolerant Networking, or DTN, to transmit dozens of space images. Wikipedia's current events log for November 19 recorded that NASA successfully tests the first deep-space communications protocol to pave the way for Interplanetary Internet.

The effort required a long-term collaboration to rethink how data moves. NASA and Vint Cerf, a vice president at Google Inc., in Mountain View, Calif., partnered 10 years ago to develop this software protocol.

How Disruption Tolerance Changes Network Architecture

The NASA release named some of the causes: glitches can happen when a spacecraft moves behind a planet, or when solar storms and long communication delays occur. It drew the contrast plainly: unlike TCP/IP on Earth, the DTN does not assume a continuous end-to-end connection.

Instead, the release said, each network node keeps the information as long as necessary until it can communicate safely with another node.

One way to read this is that reliability can rest with each step of a chain rather than with the link between them. When conditions cannot be smoothed out, it may make sense to design around them rather than against them.

Perhaps resilience begins with planning for the moment a connection breaks.

Sources