Why not use the connection ID for encoding the PN? Mikkel
On 16 November 2020 at 19.12.02, Christian Huitema ([email protected]) wrote: Kazuho, You are proposing to use a transform, in which the AEAD "sequence" is the conjunction of a sequence number space identifier and the number within that space. I agree that doing that solves the uniqueness requirement, but I have two concerns. First, your original proposal allocates just 2 bits for the sequence number space identifier. You observe that the sequence number is encoded as a varint, which can only encode 62 bits of value, and thus we can reuse the two high order bits to encode a number space identifier. But what happens if the connection uses more than 4 number spaces? Second, we have a synchronization issue. At what point do nodes start using the "path-specific" number space? If we want to be robust, don't we need to encode a number space identifier in the packet header? -- Christian Huitema
