I thought this was about actual interplanetary networking. Can we change the title to be less clickbait and more informative?
It relies on the page Reserved_IP_addresses, implying that a martian is a packet with a source address within certain ranges. In fact a martian is a packet with a source address for which the receiving interface isn't configured; any address could be a martian, depending on how the interface is set up.
Hey, if I'm wrong, please set me straight.
What you're talking about is referred to as source address validation [2] also known as strict reverse path forwarding (RPF) [3].
[1] https://datatracker.ietf.org/doc/html/rfc1812#section-5.3.7
[2] https://datatracker.ietf.org/doc/html/rfc1812#section-5.3.8
[3] https://datatracker.ietf.org/doc/html/rfc3704#section-2.2
A quick usenet search shows references to the term back into the 90's.
A contemporary definition that is not self-contradictory is in Eric S. Raymond's New Hacker's Dictionary, published four years earlier; but which isn't what RFC 1812 says either, however.
So whilst the people who weren't alive in the 1990s are wrong to be hung up on the "I thought it meant 'from Mars'." confusion, since the saddening reality of 2023 is that we're no nearer to that being a realistic source of confusion than we were in 1991; the obverse of the coin is that, like much of the Jargon File, it's woolly slang set over-hard into stone by Eric S. Raymond and a document from Cisco that it is unwise to rely upon for strict technical meaning.
There’s a Mars Fleet of about 11 operational spacecraft and robotic landers/rovers/etc on or around Mars right now, and in fact the robotic helicopter, Ingenuity, runs Linux. I legitimately thought it was related to those. There were no operational missions at Mars in 1991.
NASA already sends most data from Mars surface assets to Earth by relaying through Mars satellites (including ESA satellites that NASA provides their Electra radio to), and it's starting to get crowded out there. NASA is gearing up for Mars Sample Return (for which they've already cached samples): https://www.youtube.com/watch?v=t9G36CDLzIg
(And, in fact, Ingenuity, which runs Linux, actually sends its images to the Perseverance rover via radio, which transmits to orbiting Mars satellites, which then transmit to Earth... it's becoming a non-trivial network.)
After that will come crewed missions, maybe starting with orbit (perhaps teleoperating assets on the surface) before surface missions. The number of entities involved on Mars has grown pretty dramatically, with not just NASA, but Europe (ESA), China (rover and orbiter, is planning a sample return mission as well), United Arab Emirates (has an operational satellite right now), India (just concluded their satellite mission about 6 months ago after operating 8 years), and there's starting to be private missions as well, such as Impulse Space and Relativity's 2026 mission and whenever SpaceX gets around to sending Starlink satellites (perhaps for NASA...) or Starship or maybe Lockheed doing the same thing, as they've planned for the Moon ( https://gizmodo.com/lockheed-martin-spinoff-satellite-conste... ).
There's every reason to think there will be more and more need for sophisticated networking technology in deep space, including on Mars.