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HOLD, RETRIEVE, Explicit Call Transfer

From: Emeka Mosanya <emeka.mosanya@ubicall.com>
Date: Wed, 19 May 2004 14:51:22 +0200
To: <www-voice@w3.org>
Message-ID: <00a901c43d9f$fd4c58b0$6c00a8c0@ubicall.com>

Dear all,

After reviewing CCXML Version 1.0 Last Call Working Draft,
I was surprised to not find any construction for the call
OnHold and Retrieve call control functionality.

This functionality is largely used in directory dialing
application where we want to put the caller on hold while
we are dialoging with the called party, for example during
interactive call filtering IVR.  

Without OnHold and Retrieve functionality, we are forced
to use the first port to play the waiting music and open
a new port to contact the called party, using two often
expensive port, when only one would be required.  This
correspond to the Personal Assistant example (11.3).

Moreover, again in directory dialer applications, if the
called party accept the call, we must connect the caller
and the called party, and release corresponding telephony
resources.  Therefore, no telephony resources are used when
the two call party are talking to each other (excepted switch
or PBX resources). This correspond to the call transfer part.

Current CCXML model assume that all everything works using
tromboning/bridging.  In my experience, our customers are
very sensitive when we talk about the quantity of used port.
Often, they do not like tromboning.


One could express the OnHold, Retrieve, and Explicit Call
Transfer by allowing several Connection to share the same
media resource. This can be expressed in ccxml by adding
the notion of hold group (Other term than "hold group" could

Now, by adding few attribute to existing <unjoin>,
and <createcall>, and by extending the semantic of join, we
have the required behaviour.

  hold: optional boolean that indicate if the Connection that is
        unjoined should be put on hold.  Note: this correspond to
        the hook-flash function you may encounter on your handset
  holdid: optional id that identifies the "hold group". 

  holdid: optional reference to an existing "hold group" id that
          indicate that the new call will share the unique media
          resource associated with this "hold group".  Note: this
          correspond to dialing a new correpondant after you have
          made a hook-flash, for example. The on-hold connection
          and the newly created connection share the same telephony

  Added semantic: 
    - if the two Connections belong to the same "hold group",
      then join the two connections at switch/PBX level (no bridging).
      The two connections are considered as disconnected at ccxml
      engine level.
    - if the two Connections do not share the same telephony resource,
      retrieve the Connection(s) that are on-hold and join them as

Hold, Retrieve and Transfer are feature that are really important to
company building directory dialer.  Without them, ccxml loose most of
its interest.

Best regards,

Emeka Mosanya
Emeka Mosanya, Ph.D               Ubicall Communication s.a.
VP Engineering                    http://www.ubicall.com
mobile: +32 477877372             fixed: +32 65 321534
Received on Wednesday, 19 May 2004 08:55:34 UTC

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