Hi,
If branch parameter got introduced in 3261 and this MUST be GUID.
>From 3261:
The branch parameter value MUST be unique across space and time for
all requests sent by the UA. The exceptions to this rule are CANCEL
and ACK for non-2xx responses. As discussed below, a CANCEL request
will have the same value of the branch parameter as the request it
cancels. As discussed in Section 17.1.1.3, an ACK for a non-2xx
response will also have the same branch ID as the INVITE whose
response it acknowledges.
The uniqueness property of the branch ID parameter, to facilitate
its use as a transaction ID, was not part of RFC 2543.
Thanks,
Neel.
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Roman
Shpount
Sent: Friday, September 30, 2016 10:19 PM
To: Alex Balashov
Cc: [email protected]
Subject: Re: [Sip-implementors] Arbitrary Via parameters
On Fri, Sep 30, 2016 at 5:38 PM, Alex Balashov <[email protected]>
wrote:
> On 09/30/2016 03:52 PM, Roman Shpount wrote:
>
> As far as Via is concerned, the better and standard compliant
>> practice is to encode any application specific data in VIA tag
>> parameter using some sort of proprietary encryption scheme. It is
>> guaranteed that Via tag will be returned to the proxy unmodified.
>>
>
> That might conflict with the requirement that the branch parameter be
> a GUID.
>
> It's less important for transaction-identifying GUIDs than for
> something like Call-ID, but still.
Via branch parameter is the transaction identifying parameter. Its format and
contents are implementation specific. There is no requirement for Via branch
(or SIP Call-ID for that matter) to be a GUID. All that is required is that
these parameters were unique.
Regards,
_____________
Roman Shpount
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
