Re: [quicwg/base-drafts] Invariants: Unclarity in short headers (#2335)

Magnus Westerlund <> Thu, 17 January 2019 09:03 UTC

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From: Magnus Westerlund <>
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Subject: Re: [quicwg/base-drafts] Invariants: Unclarity in short headers (#2335)
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Ok, the spec is in some sense clear that this can be of arbitary length. However, that this is not required to be consistent with the long header is far from obvious and probably should be explicitly remarked. 

An realization I didn't have before over this design is that a given destination IP address and UDP port that deals with multiple QUIC connections will be foreced to use one commond DCID length across all QUIC connections using that port, otherwise it will have to use prefixes for DCIDs to be able to determine how long the actual DCID field are to enable decoding the header protection. It might have been a misstake to not include an DCID length field. 

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