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Re:43 km line of sight with USB WiFi stick (2005) by tomxor on Thursday March 03, 2022 @02:36PM (#30545662)
(Current) One-Way Light Time = 21:35:13 [0]

So 43 hours 10 minutes 26 seconds minimum, excluding processing time.

That's probably another record... Although I'm pretty sure it can't process ICMPs, so "ping" in the more general sense.

[0] https://voyager.jpl.nasa.gov/mission/status/

Re:43 km line of sight with USB WiFi stick (2005) by benbristow on Thursday March 03, 2022 @03:46PM (#30546744)
That must be fun over SSH/Telnet. 43 hours between every key press

Joking, but thanks for the interesting info (and Frost1x also).

Re:43 km line of sight with USB WiFi stick (2005) by _joel on Thursday March 03, 2022 @04:38PM (#30547382)
Come on, SSH and Telnet? That's ludicrous. It's a job for https://mosh.org/
Re:43 km line of sight with USB WiFi stick (2005) by rzzzt on Thursday March 03, 2022 @06:13PM (#30548348)
At the very least, local echo must be enabled.
Re:43 km line of sight with USB WiFi stick (2005) by mrb on Friday March 04, 2022 @06:37AM (#30553369)
Neither ICMP nor IPv4 existed when the Voyager probes were launched in 1977 :) ICMP was created in 1981
Re:43 km line of sight with USB WiFi stick (2005) by tomxor on Friday March 04, 2022 @10:46AM (#30556333)
Yeah, that's what I was implying ;D

I think an older probe also took the first digital pictures before bitmap images were a thing, they could digitise it at the probe end but had to colour in the pixels on a piece of paper at the other end if I recall correctly. Point is, NASA had to solve a lot of digital communication problems long before they had established terrestrial solutions or before computers were even capable of solving the whole problem on their own.

Then again, even if the timing was reversed, a lot of terrestrial communication protocols have no chance of working properly at the ranges required for space exploration - something I've been meaning to look into is the redundancy requirements over those long distances, since re-transmission is so costly in terms of latency that it probably makes sense to pack as much redundancy into the signal as possible, we already do this with terrestrial communication in the form of various codes, but there's a finer balance between increased bandwidth and the relatively low latency cost of re-transmission in the case of unrecoverable sequences... I'm guessing you want a far lower probability of loss for a 43 hour round trip.

Re:43 km line of sight with USB WiFi stick (2005) by tanbogy on Thursday March 03, 2022 @05:59PM (#30548204)
And I used to get angry with 250ms ping playing WoW.