Re: DTMF & SIP

Scott Petrack <scott.petrack@metatel.com> Thu, 08 July 1999 11:24 UTC

Date: Thu, 08 Jul 1999 07:25:45 -0400
From: Scott Petrack <scott.petrack@metatel.com>
To: Jacob Avraham <jacoba@mediagate.co.il>
cc: Jonathan Rosenberg <jdrosen@dnrc.bell-labs.com>, MMUSIC list <confctrl@ISI.EDU>
Subject: Re: DTMF & SIP
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There seem to be at least two different ways to encode DTMF information
now -- by an MGCP notification, or by an RTP payload. I personally would
have no problem encoding the RTP payload within MIME (of type 
audio/rtp ?) to be put within a SIP payload, but what would the purpose
really be? 

If you take the real-time info out of the DTMF, then you are left with a
string of digits. What is the purpose of transporting such a string of
digits within SIP?

Scott

On Wed, 7 Jul 1999, Jonathan Rosenberg wrote:

> This is one of the proposed uses of the INFO method, documented in:
> 
> http://www.ietf.org/internet-drafts/draft-ietf-mmusic-sip-info-method-00.txt
> 
> Whether or not its actually a good idea to carry DTMF out of band is a
> good question... 
> 
> -Jonathan R.
> 
> Jacob Avraham wrote:
> > 
> > Is there any mechanism in SIP to transfer DTMF (not in the RTP stream)
> > during the call? Or, if this is outside the scope of SIP, what companion
> > protocol is used to do that?
> > 
> > Thanks,
> > 
> > Jacob Avraham
> > Mediagate
> > 
> > ---------
> > This message came from the IETF IPTEL Working Group Mailing List.
> 
> -- 
> Jonathan D. Rosenberg                       Lucent Technologies
> Member of Technical Staff                   101 Crawfords Corner Rd.
> High Speed Networks Research                Holmdel, NJ 07733
> FAX: (732) 834-5379                         Rm. 4C-526
> EMAIL: jdrosen@bell-labs.com
> URL: http://www.cs.columbia.edu/~jdrosen
>

DTMF & SIP Jacob Avraham
Re: DTMF & SIP Jonathan Rosenberg
Re: DTMF & SIP Scott Petrack