Is it allowed for a server to reuse the current CID when it notices a NAT
rebinding? I wonder if the text ("…., in which case it MAY continue to use the
current connection ID with the new remote address while still sending from the
same local address.”) indicates that the server can reuse the current CID?
Thanks.
> On Sep 26, 2023, at 02:38, Ian Swett <[email protected]> wrote:
>
> Yes, because a client is not aware of the NAT rebinding, so it would not know
> to use a different CID.
>
> On Mon, Sep 25, 2023 at 7:39 AM "杨馥榕(Personal)" <[email protected]
> <mailto:[email protected]>> wrote:
> Hello,
> I am a bit confused about whether RFC9000 allows endpoints to reuse CIDs
> under NAT rebinding. In 9.5, RFC9000 says that
> "Similarly, an endpoint MUST NOT reuse a connection ID when sending to
> more than one destination address. Due to network changes outside the control
> of its peer, an endpoint might receive packets from a new source address with
> the same Destination Connection ID field value, in which case it MAY continue
> to use the current connection ID with the new remote address while still
> sending from the same local address.
>
> These requirements regarding connection ID reuse apply only to the sending of
> packets, as unintentional changes in path without a change in connection ID
> are possible. For example, after a period of network inactivity, NAT
> rebinding might cause packets to be sent on a new path when the client
> resumes sending. An endpoint responds to such an event as described in
> Section 9.3.”
>
> Does this mean that we can reuse CIDs in the case of NAT rebinding?
>
> Best regards,
> Furong Yang
