The SBC Core acting as a P-CSCF or as an IBCF in an IMS deployment supports the following Multi-Media Telephony (MMTel) Supplementary Services:

  1. Originating Identification Presentation (OIP)
  2. Originating Identification Restriction (OIR)
  3. Terminating Identification Presentation (TIP)
  4. Terminating Identification Restriction (TIR)
  5. Communication Diversion (CDIV)
  6. Communication Hold (HOLD)
  7. Anonymous Communication Rejection (ACR)
  8. Communication Barring (CB)
  9. Message Waiting Indication (MWI)
  10. Conference (CONF)
  11. Malicious Communication Identification (MCID)
  12. Explicit Communication Transfer (ECT)
  13. XCAP over Ut interface for Manipulating NGN Services
  14. Advice Of Charge (AOC)
  15. Closed User Groups (CUG)
  16. Three-Party (3PTY)
  17. Flexible Alerting (FA)
  18. Communication Waiting (CW)
  19. Completion of Communications to Busy Subscriber (CCBS) Completion of Communications by No Reply (CCNR)
  20. Customized Alerting Tones (CAT)
  21. Customized Ringing Signal (CRS)
  22. Personal Network Management (PNM)
  23. Unstructured Supplementary Service Data (USSD)


The SBC also supports transparency of Tel URI in the Request-URI. The Request-URI is the URI representing the intended destination of a SIP request. The SBC has the ability to globalize a Request-URI (to the extent possible) before the call enters the IMS core. Request-URI types include:

  • Local number with or without phone-context, in tel or sip URL format.
  • Global number.
  • Vertical Service Code (VSC) with or without ‘user=dialstring’ – A special code dialed prior to (or instead of) a telephone number that engages some type of special telephone service. It is typically preceded with an asterisk or * (star) key.
  • Username/Alphanumeric.

The SBC can be configured to manipulate an ingress ‘user=dialstring’ parameter in SIP URI in a Request-URI to a ‘user=phone’ parameter if the PSX manipulates the number.

Conversely, SBC can be configured to transparently pass the Request-URI toward the egress call leg if PSX does not manipulate it. For example, if a VSC is dialed, the VSC is sent “as-is” toward the IMS core. Likewise, if the Request-URI has a SIP URI of the form username/alphanumeric (e.g., sip:bob@sonusnet.com), the Request-URI is sent “as-is” toward the IMS core.

The CLI syntax to enable/disable this dial string handling feature is described in the CLI Reference Guide section.


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