Transfer control tags

This section gives information about the tags that can be used in call transfer applications.

CONSULT

A SIP 'CONSULT' tag. This is used to make the outbound call of an attended call transfer.

Size
The maximum length of the tag is 256 characters.
Valid attributes
None.
Valid usage
  • The 'CONSULT' tag must be set to 0 in SV541 prior to issuing the TransferCall state table action to request that an outbound call be established. The VOIP_Call_Transfer custom server must be installed and running when using a 'CONSULT' tag
Example
CONSULT=0
TRANSFER

A SIP 'TRANSFER' tag. This invokes the REFER/REPLACES call transfer action.

Size
The maximum length of the tag is 256 characters. The tag value should be set to '0'.
Valid attributes
None.
Valid usage
  • To invoke a SIP call transfer using a TransferCall action, this must be set in SV541. This tag should be used either after the VOIP_Call_Transfer custom server has initiated an outbound call using CONSULT (and the consult phase is complete), or with any existing call as long as its call reference (SV237) is also assigned to SV541 in the CAL_REF tag.
Examples
TRANSFER=0
or
TRANSFER=0
CALL_REF=1234
CALL_REF

A SIP 'CALL_REF' tag. This is used with the TRANSFER tag to identify another existing call for which a SIP REFER/REPLACES transfer action is required. The VOIP_Call_Transfer custom server is not needed to establish the outbound call if the CALL_REF tag is used.

For example, '1234'.

Size
The maximum length of the tag is 12 digit characters.
Valid attributes
None.
Valid usage
  • To invoke a SIP call transfer on a TransferCall action in SV541. This tag should be assigned to the call reference value (SV237) of the call to which the transfer is required. The TRANSFER tag must also be assigned (see TRANSFER for more information).
Example
234568
XFER_TIMER
A SIP 'XFER_TIMER' tag can be used to set the timeout for a blind transfer.
Size
The maximum length of the tag is 256 characters
Valid attributes
None
Valid usage
  • Set in SV541 prior to invoking a blind transfer.
  • XFER_TIMER can be set to any value in the range 0 to 35. If it is set to a value greater than 35, a value of 35 will be used.
  • Set XFER_TIMER to 0 for true blind transfer to occur.
Example
XFER_TIMER=0