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Towards Interplanetary QUIC Traffic

105 points by wofo

by nopurpose

1 subcomments

Having worked with QUIC extensively lately I must say that having protocol entirely in userspace is truly liberating. It also helps that almost everything, including headers is encrypted, as a result middle boxes can't interfere and "optimise" your flow.
For high latency and high packet loss links, like one described in the article, you'll probably need pre-emptive retransmits and I am not sure that simply tuning parameters will get there. Retransmitting before loss is detected cuts bandwidth, but I suspect will improve end to end latency.

by jauntywundrkind

1 subcomments

Top heavy write-up, with lots of intro & set up. Good stuff, and was happy to see it covered.
And talks to really good really neat wins! Simulated in-process network, tapping Quinn's AsyncUdpSocket and UdpPoller. Cool, nice. Better debugging with pcap, nice. Determinism, nice.
I do want a bit more of an ending though! Glad to see the work open sourced. +1 the thanks to Marc Blanchet for all his help & pushing that push. Also very fun reading their draft (linked in post), An Architecture for IP in Deep Space, https://datatracker.ietf.org/doc/draft-many-tiptop-ip-archit...
> How can QUIC be viable, then? The attentive reader might already have spotted the answer: the problem isn’t QUIC, but its default configuration, which was designed with terrestrial internet in mind. What we need is a custom configuration, this time targeting deep space, with guidelines to tweak things further if a space mission deems it necessaryy.
I'd expect that there's a ton of work for "bandwidth shaping" interplanetary QUIC that's probably missing, even if it just needs to be basically nulled out on the way across the x-mitters. Guess it's open source & I can dive in & see what was done here!

by Veserv

1 subcomments

The problem with QUIC for these kinds of problems is that it is really multiple protocols stacked in a trenchcoat with no way to get at the individual layers.
QUIC has a connection setup protocol, a stream reconstruction protocol, a stream management protocol, a adaptive channel parameter discovery protocol, a resend protocol, a channel bandwidth distribution protocol, and probably a few more that I can not think of off the top of my head just for normal stream oriented transport.
What you really want in this sort of use case is most things except adaptive channel parameter discovery (i.e. half of congestion control). You should already know the expected channel bandwidth and latency and can instead adapt in-context rather than using totally generic mechanisms designed under the assumption of a “uniform/static” network.

by xvilka

1 subcomments

We don't have proper interplanetary time standard yet[1][2][3]. That should be a first big milestone to achieve standardized networking with all space objects at least in the Sol system.
[1] https://science.nasa.gov/learn/basics-of-space-flight/chapte...
[2] https://bidenwhitehouse.archives.gov/ostp/news-updates/2024/...
[3] https://space.stackexchange.com/questions/5540/has-an-interp...

by throw0101c

0 subcomment

by juancn

4 subcomments

Why not a store-and-forward architecture?
You still need a protocol for point to point and maybe that's where QUIC plays a role, but wouldn't make more sense to use something like email?
The distances and latencies are so large, that you want to send a file to the next hop in the network, and from there to the next one, and so on.

by incognito124

1 subcomments

by mannyv

1 subcomments

QUIC might be great, but what about the PHY layer? How are they simulating that? Can the PHY later handle packets that take forever to arrive? And what happens if you have half a packet?
How would this compare to, say, using the same stuff that the Ham guys use? They were doing IP over slow links decades ago.
And really, why use QUIC or IP at all when it's literally point-to-point traffic? Just send tagged chunks using the simplest, dumbest protocol possible.

by creatonez

3 subcomments

> Intermittence is mostly a consequence of using orbiters as communication relays to reach a planet’s surface. Orbiters go around the planet and are only able to communicate with peers they can “see”.
As I understand, this type of intermittence will mostly be a solved problem by the time there are only a few relay satellites around a planet. I think the moon may already have enough for full coverage. (It does not have to be a full-on starlink-like network, Musk is a bit delusional about this)
Still interesting and potentially useful to design around it regardless.

by Scott-David

0 subcomment