Subject: [mediactrl] MSCML: reserved minimum conference talkers

From: "David Cromwell" <[email-masked]>
Date: Fri, 21 Apr 2006 16:38:48 +0100

<span
style='font-size:10.0pt'>Currently the spec does not provide for a reserved
minimum number of conference talkers.   Rather than specify a maximum
number of talkers, it would seem to be more useful to for client to create a
conference with a reserved minimum number of talkers.   

<span
style='font-size:10.0pt'> 

<span
style='font-size:10.0pt'>Consider the case of a meet-me conference for five
talkers, where conferees dial in at some scheduled time in the future. 
 The client would create a conference with five talkers reserved.  If
during the conference, a sixth conferee needed to be added in, the server would
honor the request as long as there was a spare resource available.  

<span
style='font-size:10.0pt'> 

<span
style='font-size:10.0pt'>Generally speaking, it is useful for conferences to be
able to grow dynamically beyond the reserved minimum resources as long as there
are available resources on the media server. 

<span
style='font-size:10.0pt'> 

<span
style='font-size:10.0pt'>Draft-vandyke-mscml-07 says that  "when the
reservedtalkers+1st INVITE arrives at the media server, the media server MUST
generate a 486 Busy Here response."  This rules out any dynamic
expansion of a conference beyond the initial slice of reserved resources. 
A reserved maximum attibute forces the client to reserve more than the number
of resources it thinks it needs in order to cover any conferees that might need
to be added into the conference dynamically.  The reserved maximum
concept encourages overbooking of conferencing resources and potentially reducing
the conferencing capacity on the server.

<span
style='font-size:10.0pt'> 

<span
style='font-size:10.0pt'>A reserved minimum attribute lets the client reserve
only that number of resources it needs, and also gives the possibility of
expanding the conference dynamically if additional resources are available.
  The reserved minimum concept encourages efficient use of
conferencing resources.

<span style='font-size:
10.0pt;font-family:Arial;color:windowtext'> 

<span style='font-size:
10.0pt;font-family:Arial;color:windowtext'>Regards,

<span style='font-size:
10.0pt;font-family:Arial;color:windowtext'>David

<span lang=FR
style='font-size:10.0pt;font-family:Arial'>-- 

<span lang=FR
style='font-size:10.0pt;font-family:Arial'>[email-masked] 
AudioCodes, Inc.
633 Davis Drive, Suite 300 
Durham, NC 27713 

<span
lang=FR style='font-size:10.0pt'>