[quicwg/base-drafts] Connection ID Length changes (#2473)

martinduke <notifications@github.com> Fri, 15 February 2019 17:33 UTC

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Subject: [quicwg/base-drafts] Connection ID Length changes (#2473)
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There's nothing in the spec that prohibits this, except from zero to not zero. But should there be?

1) For the receiver, it's a bit annoying to have to store the length of each additional connection ID
2) We could eliminate the length field from the frame
3) If we're concerned about changes from zero-length being detectable, we should also be concerned about length changes being detectable. Ultimately, the complexity of handling this is the problem of the endpoint generating the connection ID, so if you want to do this to yourself, go for it. The use case for going from zero to not-zero (unexpectedly needing migration) is as relevant as changing between non-zero lengths (migrating existing connections when the routing scheme totally changes)

I would recommend one of the following:
A) New CIDs must retain the same length
B) Remove all restrictions on CID length changes - I sorta lean towards this one,  but I think both are better than the status quo.

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