It's simply a matter of implementors reporting.  The key point is that the Working Group Chair has to know exactly which features of the RFC were tested and which not.  In the case of the G723 payload type, there are no options to worry about: it's simply a matter of different implementations agreeing on RTP payload type 4 and subsequently transmitting RTP-encapsulated packets in accordance with G.723.1, using one frame (30 ms) per packet or such other value as specified by the A:ptime attribute.
-----Original Message-----
From: Rex Coldren [mailto:coldrenr@AGCS.COM]
Sent: Wednesday, March 14, 2001 2:37 PM
To: ITU-SG16@MAILBAG.INTEL.COM
Subject: Re: FW: [VoIP-list] FW: [Fwd: AVT WG last call on RTP spec and profil e]

Francois,

I believe you are correct.  However, I am not familiar with how the IETF determines
"interoperable implementations".  Is is simply a matter of vendors reporting with whom
they interoperate or is there some IETF-sponsored interop event that needs to be
attended?

Rex

Francois Audet wrote:

 Guys,This payload type = 4 for G.723.1 has been in H.225.0 for many years. Don't we have many interoperable H.323 products using PT=4 for G.723?Won't it be a major interoperability problem if this payload type is removed from the A/V specification?????> -----Original Message-----
> From: Simao Campos-Neto [ mailto:simao.campos@LABS.COMSAT.COM
> <mailto:simao.campos@LABS.COMSAT.COM> ]
> Sent: Friday, March 09, 2001 8:27 AM
> To: ITU-SG16@MAILBAG.INTEL.COM
> Subject: [Fwd: AVT WG last call on RTP spec and profile]
>
>
> Dear colleagues,
>
> please see in the attached that audio payload formats for G.723.1,
> called there "G723", has been removed from the latest RTP A/V profile
> because of the lack on information that interoperable implementations of
> them exist. Other audio payload formats have also been removed, e.g.
> H263 (this is not the same as H263-2000), GSM-HR, GSM-EFR, If you know
> of such implementations, there is still some VERY short time (less than
> 2 weeks) before the IETF issues the repeat WG last call. Please provide
> any such information directly to Stephen Casner <casner@acm.org>.
>
> Best regards,
> Simao.