KT%20Internet%20Call%20Waiting%20Service

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KT Internet Call Waiting Service

• lt draft-rhim-spirits-kticw-00.txt gt
• Sung Yurn, Rhim
• IN Research Team
• Korea Telecom
• syrhim_at_kt.co.kr

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Contents

• Service Features
• Architecture
• Architectural Features
• Protocols
• Extension of PINT Protocol
• Pros and Cons
• Further Challenges

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Service Features

• Internet On-line Trigerring
• Incoming Call Notification
• - Calling Party Number/Name/Time Identification
• Incoming Call Handling
• - Accept/Reject/Forward to Another/Forward to VMS
• - Call Processing on No Response
• - Automatic Call Disposition
• Call Logging
• Automatic/Manual Service Activation/Deactivation
• ICW Client Configuration

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Architecture
Internet
PSTN
SCP
ICW Proxy
ICW SL
ICW UAC/UAS
ICW Server System
firewall
SCF /SDF
SCGF
PINT
firewall
INAP
IP
SSP
PINT
SRF
SSF /CCF
ICW UAC/UAS
LEX
CCF
ICW Client System ICW Subscriber (callee)
SL Service Logic UAS User Agent Server UAC
User Agent Client INAP Intelligent Network
Application Protocol PINT PSTN/IN Interworking
Protocol
PINT Protocol SCP Internal Protocol INAP Protocol
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Architectural Features

• SCGF on SCP
• - has protocol interworking function
• ICW Server System
• - has proxy server function for message routing
• - has management function for the ICW Clients
  connected to it
• ICW Client Application on subscribers PC
• - monitors and notifies internet connection
  status to the SCP
• - disconnects the modem connection to accept the
  incoming call
• - has service profile with automatic call
  processing info.

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Protocols
PINT Proxy
PINT UAS
PINT UAC
PINT UAC
PINT UAS
SSP
PINT 1.0
PINT 1.0
ICW Server System
ICW Client System
SCP
INAP CS-1
IP
REGISTER
INVITE

• KT INAP 1.0
• based on ITU-T INAP CS-1
• Added two CS-2 INAP messages(PRM, EM)
• PINT 1.0
• PINT Service Protocol by IETF PINT WG
• Based on SIP 2.0 and SDP

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Extension of PINT Protocol

• REGISTER
• - registers/unregisters the internet on-line
  status to PSTN
• - shows the liveness of the client/internet
  connection
• Bye
• - conveys the Call Processing Result from PSTN
• Responses to INVITE
• - 100 Trying Trying
• - 200 OK Accept the Call
• - 303 See Other Forward the Call to Another
  Number
• - 380 Alternative Service Forward the Call to
  VMS
• - 603 Decline Reject the Call

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Pros and Cons

• IAP Independent
• -gt No pre-arrangement between IAP and SP
• Supplementary Service of TMS
• -gt increase the call completion rate for busy
  subscriber
• -gt dedicated to the subscribers telephone
  number
• -gt not support subscribers mobility
• Accept the Call via PSTN not VoIP
• -gt Automatic Modem Disconnection Feature

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Further Challenges

• Virtual Second Line Feature
• -gt accept the call via VoIP
• Extend the ICW Service to general messaging
  service such as UMS, community services, etc.