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A story about bypassing air Canada's in-flight network restrictions

(ramsayleung.github.io)
164 points samray | 1 comments | 10 Oct 25 07:50 UTC | HN request time: 0.208s | source
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ajd555 ◴[10 Oct 25 11:52 UTC] No.45537856[source]▶
If a ping to a specific IP times out, I wouldn't say the IP is blocked. It could be that ICMP specifically is blocked, following some network rules on the firewall. This is pretty common in entreprise networks to not allow endpoint discovery. I could be missing something and happy to be corrected here, but I was surprised to read that.
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EvanAnderson ◴[10 Oct 25 13:03 UTC] No.45538538[source]▶
I find it's important to remember, too, that a failed PING tells you nothing other than your echo request did not receive a response. If the remote host received your request, and if it responded, are both things a failed PING can't tell you, because both of those things could be true but you still end up with a failed PING.

I've seen technicians get tripped up in troubleshooting thinking that a failed PING tells them more than it does. When the possibility of asymmetric return paths is involved it's always important to remember how little a failed PING actually tells you.

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jacquesm ◴[10 Oct 25 13:55 UTC] No.45539109[source]▶
And that can be a lot more subtle than you might think. I've had a persistent very hard to debug false alarm triggered on pings sometimes not making it and most of the time they did. But very rarely that would happen three times in a row and that was the threshold for raising an alarm. We spent days on this. Finally, the root cause was tracked down to a BNC 'T' connector at the back of a media adapter that filtered out the header of some percentage of ICMP packets. It is one of the weirdest IT problems I've ever encountered and it makes me wonder how much of what we rely on is actually marginal.
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ceejayoz ◴[10 Oct 25 14:49 UTC] No.45539715[source]▶
> It is one of the weirdest IT problems I've ever encountered and it makes me wonder how much of what we rely on is actually marginal.

Vernor Vinge had a character who was a "Programmer-Archeologist" on a relativistic starship. Feels more and more prescient as time goes on.

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pbh101 ◴[10 Oct 25 15:07 UTC] No.45539906[source]▶
I thought that too up until this GenAI moment, and now I wonder if needing to be an archaeologist will be so valuable if one can get your needs met by a quickly GenAI-written script/program.
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1. palmotea ◴[10 Oct 25 18:40 UTC] No.45542304[source]▶
> I thought that too up until this GenAI moment, and now I wonder if needing to be an archaeologist will be so valuable if one can get your needs met by a quickly GenAI-written script/program.

I never have actually read those books (though I read some summaries about them, interesting concepts). My understanding is the "programmer-archeologists" basically had an archive of massive quantities of very high-quality software that did pretty much anything you'd want software to do. So it made more sense to find the software you need and glue it together than write from scratch.

And given GenAI doesn't write high quality software (at least not yet, and hopefully never), I don't think that "GenAI-written script/program" would be a good replacement (though an AI archeologist might make more sense, with such an archive).