SRVCC (Single Radio Voice Call Continuity) provides the ability to transition a voice call from the VoIP/IMS packet domain (LTE) to the legacy circuit domain. Variations of SRVCC are being standardized to support both GSM/UMTS and CDMA 1x circuit domains. For an operator with a legacy cellular network who wishes to deploy IMS/VoIP-based voice services in conjunction with the rollout of an LTE network, SRVCC offers VoIP subscribers with coverage over a much larger area than would typically be available during the rollout of a new network.

Use Srvcc parameter to configure SRVCC functionality. Zone - Srvcc is available to enable/disable EATF functionality for a zone.

To View and Edit Srvcc

On SBC main screen, go to All > Global >  Signaling > Srvcc. The Srvcc window is displayed.

Figure 1: Srvcc

The following fields are displayed:

Table 1: Srvcc Parameters

Parameter Default ValueDescription
Stn SrNULLRequest URI for a transfer call sent by MSC on PS to CS call handoff.
E Stn SrNULLRequest URI for a emergency transfer call sent by MSC on PS to CS call handoff.
Atcf URINULL

SIP URI to be used as the ATCF Path and Management URI

Pstops Sti
NULL

Request URI (0-32 characters) for a PS to PS optimized handover call. The allowed character set is:

  • Alphabets(upper- and lower-case)
  • Numbers (0-9)
  • Any of the following special characters:
    • +
    • -
    • .
    • (
    • )

For example, +1-pstopsSti-222 is a valid value for this field.

Call Linger Timer8Number of seconds to wait for INVITE due to STN_SR before clearing the call.

Make the required changes and click Save at the right hand bottom of the panel to save the changes made.



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