Bounding UDP payload size to 1200 and renaming - #1156
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Just need to fix up the formatting a bit, then I'm happy to merge this. |
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Would you mind squashing the formatting fixes into the first commit? Should be easy with an interactive rebase. |
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As mentioned in #1154, it seems quinn sends UDP datagrams with a payload 1232 bytes by default.
This is easily reproducible with the client.rs/server.rs quinn example, making a GET request and serve a reasonable big file.
Looking at the QUIC spec, (quic-draft-32 #14) , it seems the protocol should supports networks where the maximum UDP payload is 1200 bytes.
Any larger value should be discovered using PMTUD.
This PR contains two changes:
const MIN_MTU: u16 = 1232;intoMAX_INITIAL_UDP_PAYLOAD_SIZE. This change has no impact from the semantic point of view. The rationale behind this change is because that value seems to be used across the code to compute what in QUIC is defined as "the maximum datagram size" (i.e., the UDP datagram payload).1232to1200and avoid quinn assembles packets (UDP datagrams) with a payload greater than this value.