A SIP Call Control Model draft-mahy-sip-cc-models-00.txt

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A SIP Call Control Modeldraft-mahy-sip-cc-models
-00.txt

• Rohan Mahy
• rohan_at_cisco.com

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What is Call Control?

• Manipulation of session and media relationships
  to effect the experience of the participants
  within a "conversation space"
  (typically actions
  like adding and removing participants)
• Conversation Space?
• The set of participants who have access to all
  the media sent in the context of that space
• Participants?
• Send original media, or receive and terminate
  media (a mixer is not a participant)

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Related Definitions

• Call
• All participants in a session invited by a common
  source
• Call-leg
• Pair-wise signaling relationship between two SIP
  user agents
• Conference
• Multimedia session identified by a common session
  description
• Session
• Set of multimedia senders and receivers and the
  data streams flowing from senders to receivers

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Examples

• Simple 2-party call
• 1 call, 1 leg, 1 conf, 1 session
• Locally mixed three-way call
• 1 or 2 calls, 2 legs, 2 confs, 2 sessions
• Dial-in conference
• 4 calls, legs, confs, sessions
• Multicast conference
• 1 to 4 calls, 4 legs, 1 conf, 1 session

A B
A C B
A C B D
A C B D
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Call Control Actions
B C
A B
A C B
C B
transfer
insert
C B
A B
A B
C D
A C B D
take
split
A B
A C B
A B C
A B
add
near fork
A B
B A C
A C
A C B
B C
local join
far fork
From the point of view of participant A
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Additional Requirements

• Presenting information to participants
• Use Jonathan's conference-info package?
• Handling based on special participants
• Provide participant information as in Caller
  Preferences
• Human/Robot
• Active/Passive
• Visible/Hidden
• ltasbestos-suitgt Billing? lt/asbestos-suitgt

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Proposal and Next Steps

• Move overall model definition into
  cc-framework
• New drafts implementation of actions using 3pcc
  and peer to peer primitives (for both central
  and locally mixed conference resources)
• Additional work for participant information,
  hidden/passive participants. What about billing?
• Does this belong in SIP or SIPPING?

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Thank You