Mastodawn

Julia Evans Jun 19, 2024

when I asked people to explain how UDP works I got a lot of answers to the effect of "it's spray and pray"

but I'm having trouble thinking of examples of UDP-based protocols that actually work in a "spray and pray" way —

* DNS is "send 1 packet, retry if you don't get a reply”
* QUIC is a sophisticated system for streaming data over UDP
* I'd guess that video protocols correct for packet loss
* maybe statsd is a "spray and pray” system?

(please do not reply to this explaining how UDP works)

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Liam Jun 19, 2024

@b0rk we use UDP with UHD as well as internal protocols to stream IQ (radio data) to software defined radios. Though other protocols like IIO get by with TCP so it isn't strictly necessary.

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Liam

@b0rk I should add that often these protocols don't do their own layer of acknowledgements because the IQ will already have been transmitted by the time we can correct a dropped packet. Also, in some situations the UDP IQ transfer is happening within the device so dropped packets are very unlikely.