Re: [Sipping] Question on draft-ietf-sipping-v6-transition-07

["Elwell, John" <[e-mail]>]

Vijay,

A follow-up question on the statement:
"For this, IPv6 implementations MUST use a domain
       name within the .invalid DNS top-level domain instead of using
       the IPv6 unspecified address (i.e., ::)."
Presumably just "invalid" (alone, as opposed to "xxxx.invalid" would be legal?

John 

> -----Original Message-----
> From: Vijay K. Gurbani [mailto:[e-mail]] 
> Sent: 28 January 2010 20:10
> To: Elwell, John
> Cc: [e-mail]
> Subject: Re: [Sipping] Question on draft-ietf-sipping-v6-transition-07
> 
> Elwell, John wrote:
> > [JRE] Thanks, Vijay. However, RFC 3264 specifies only 
> 0.0.0.0 for the
> > case where the address is not known in the initial offer (I am not
> > talking about the deprecated use for hold). It does not specify
> > .invalid, so I don't know what you mean by two alternative 
> solutions.
> 
> Correct; rfc3264 does not specify .invalid.  sipping-v6-transition
> is supposed to update rfc3264 to do so.
> 
> The two alternative solutions are supporting "::" and ".invalid";
> since at the time of writing of sipping-v6-transition, there
> wasn't much IPv6 support, instead of mandating both ".invalid"
> and "::", we decided to mandate only the ".invalid".  Older,
> IPv4 endpoints could continue using "0.0.0.0" while newer
> IPv4/IPv6 endpoints will use "0.0.0.0" when communicating
> with IPv4 peers and ".invalid" when doing so with IPv6 peers.
> 
> Thanks,
> 
> - vijay
> -- 
> Vijay K. Gurbani, Bell Laboratories, Alcatel-Lucent
> 1960 Lucent Lane, Rm. 9C-533, Naperville, Illinois 60566 (USA)
> Email: vkg@{alcatel-lucent.com,bell-labs.com,acm.org}
> Web:   http://ect.bell-labs.com/who/vkg/
>