The Internet: An Expansion to the Moon and Beyond

As I've often mentioned in seminars, I've been a fan of space development since I was a child and even worked in the space industry for a while after graduating from college. Even now, at over 50 years of age, I still have a strong interest in space development, so it was only natural that I attended the Internet x Space Summit, a special Interop event held recently at the Makuhari Messe exhibition center.

Across several sessions, one of the common key terms I heard was "delay/disruption-tolerant network (DTN)" - a network that's designed to operate effectively in both extreme conditions and over very large distances. The Artemis program, the first manned lunar exploration program since the Apollo program, is currently proceeding at pace. If humans are to stay on the Moon or Mars for extended periods of time, DTNs will become increasingly important.

The distance between the Earth and the Moon is approximately 380,000 km. Since the speed of light is about 300,000 km/second, a simple calculation shows that it takes about 2.5 seconds for a communication exchange between the Earth and the Moon. Although 2.5 seconds may not sound too long, the correspondence required to display a web page requires more than one exchange.

Even if an astronaut on the Moon were able to access the Web, he or she would have to wait at least 10 seconds for a page to be displayed. This is an unbearable amount of time, even if you can only imagine it. If we're talking about Mars rather than the Moon, the latency will be measured in minutes, although exact time frames will vary greatly depending on the planet's position relative to Earth...... communication must be achieved over ultra-long distances where such long delays are unavoidable.

In addition to ultra-long distances, there is also the need to address another issue: communication outages. This is why a DTN, which does not assume a continuous network connection, is essential. As a communications protocol to realize a DTN, the Bundle Protocol (BP) has already been standardized as RFC 9171, and, as I understand, various demonstration projects are currently underway.

The history of research in this area, the so-called Interplanetary Internet, is surprisingly long - dating back to 1998. It began at NASA's Jet Propulsion Laboratory, where Vinton Cerf, considered one of the "fathers of the Internet," jointly led a team with the late Adrian Hooke.

Listening to the talk about DTNs and BPs, I was reminded of the importance of interoperability and standardization activities for this purpose. As the sphere of human activity advances to the Moon and Mars, I found it extremely encouraging to learn of current cross-border discussions and demonstrations on how to best form a communications network to support such expansion.

As there are many instances where technology developed for space development is later used to resolve solutions in our world, I also hope that DTN-related technologies will be utilized on Earth. Regarding such DTN-related technologies, I have heard about actual examples of such application and social implementation (such as reindeer tracking in Sweden and taking environmental measurements from inside a Slovenian cave etc.).

Space and the Internet share a commonality in that they have no borders, or at least little geopolitical risk. I believe that the key to the sustainability of human civilization lies in how well both can be utilized in the future. In closing, the Internet x Space Summit has further strengthened such sentiments.