December 29, 2000, 2:15 PM — Earlier this year, a NASA satellite used the Internet to phone home. Hardly an earth-shattering event -- or was it?
The call was made possible by OMNI (Operating Missions as Nodes on the Internet) engineers at NASA's Goddard Space Flight Center, who uploaded standard Internet software to an orbiting UoSAT-12 satellite and then received data via the Web. It worked, which didn't surprise the engineers. What it means, however, is that NASA satellites can have their own IP addresses and send and receive Internet messages and data. That's brand-new for space jockeys.
With NASA's current system, the Consultative Committee for Space Data Systems (CCSDS), transmissions are routed to special boxes and then to a protocol for Level 0 processing. After that, the data goes out.
"It's not that IP is better or worse [as a networking tool]; it's that CCSDS is just not compatible with the rest of the planet," says Ron Parise, a senior scientist at Computer Sciences Corp. (CSC) in El Segundo, Calif.
The glitch, Parise says, is that the CCSDS protocol doesn't have a network layer. Hurdles such as intermittent connectivity and noisy links seemed insurmountable, particularly when every project had customized protocols.
While the scientific world was stymied, private companies, which faced the same problems, forged ahead, solving forward-error correction problems and developing ricochet modems.
The OMNI team says that it's confident that commercial security products will also provide sufficient protection and privacy for NASA projects.
"The bottom line is that adequate measures are available now," says James Rash, OMNI project manager. "International stock markets and financial institutions use the open Internet for trillions of transactions every day. Those security measures are available to us."
As an added precaution, using closed communications channels -- a traditional NASA operation -- remains an option, even with standard IP.
The UoSAT-12, sent up last year by U.K.-based Surrey Satellite Technology Ltd., was chosen because it already uses high-level data-link control framing. Porting an IP stack to one of the spacecraft's onboard processors was a simple task.
The network approach is producing winning scenarios. Scientists are already familiar with the Internet's capabilities; collaborative science missions are possible because IP provides a common link. For example, earth-science mission data that's retrieved from sensors in ocean buoys or balloons can be relayed from the sensors to satellites, which can then be easily accessed by scientists.
Another mission advantage is commercial IP's ability to significantly reduce integration costs. Currently, instrumentation developed in one lab travels to where a spacecraft is being built. Teams of engineers must spend weeks on interphase documents to communicate among sites.