Re: [MMUSIC] (Rough) Consensus Call - No FQDN support in ice-sip-sdp

[Roman Shpount <[e-mail]>]

On Mon, May 20, 2019 at 6:38 PM Christer Holmberg <
[e-mail]> wrote:

> I am fine with option 2. I just wanted to remind the community what it
> means for mDNS, to avoid any whoops-we-didn’t-think-of-that’s further down
> the road.
>
>
>
If FQDN is allowed but ignored, this will allow "legacy" implementations to
interop with ICE implementation which support mDNS or generic FQDN. How
FQDN are resolved and how ICE agents specify to each other the these
procedures are supported can and should be part of mDNS or generic FQND
support draft. If I am missing something and something else is required,
mDNS authors should comment.

So far this is my proposal for ice-sip-sdp connection address definition
which should implement option 2:

<connection-address>: :: is taken from RFC 4566 <<RFC4566>>. It is the IP
address of the candidate, allowing for IPv4 addresses, IPv6 addresses, and
fully qualified domain names (FQDNs).  When parsing this field, an agent
can differentiate  an IPv4 address and an IPv6 address by presence of a
colon in its value - the presence of a colon indicates IPv6.  An agent MUST
ignore candidate lines that include candidates with FQDN or IP address
versions that are not supported or recognized.  Handling of FQDN addresses
in candidate can be defined in the future specification. If candidate with
FQDN <connection-address> is the default destination/candidate, the the
"c=" address type MUST be set the IP address family for the FQDN DNS
resolution result and the "c=" connection address MUST be set to FQDN.
Differences in the "c=" line address family and type with FQDN resolution
result MUST not cause ICE support verification failure.


Regards,
_____________
Roman Shpount