CVP refer transfer

Call Transfer Using SIP Service You can configure the SIP Service to operate in two modes to perform Unified CVP transfers. Unified CVP remains in the signaling path for the duration of the call, and in this normal mode it uses SIP re-INVITE messages to perform the transfers. This causes Unified CVP to hold the port license for the call duration. To operate in standard re-INVITE mode, you do not need to modify the Unified ICME script. However, to send a REFER transfer, send a dynamic label with the letters “rf” prepended to it. Or, when using a Queue node in the Unified ICME script, define an ECC variable called "user.sip.refertransfer" and set it to the value of the lowercase "y." Unified CVP then uses the REFER method to blind transfer to agent labels. Alternatively, Unified CVP can perform a SIP REFER type transfer where it moves out of the signaling path after sending a referral to the caller to the label that Unified ICME provides. This allows Unified CVP to release the port license after the REFER is sent. Unified CVP receives notification of the outcome of the call using SIP NOTIFY messages, and this is included in the reporting database. When using REFER, do not apply the survivability script for TDM callers on the Ingress gateway. Also, SIP transfers to VoiceXML gateways for micro-applications do not use the REFER method. It is only used for non-"SEND TO VRU" type transfers. When using REFERs, note that the survivability script does not currently support REFER messaging events, so when using REFER with TDM calls on the IOS gateway, the survivability service must be removed from the pots dial peer for those calls. REFER is used as a "blind refer" operation and can typically be used when sending calls to third-party ACD agents. However, it can also be used to send calls to the Cisco Unified Communications Manager (Unified CM) extensions as well, if desired