Mitel 6867i Premium, Administrator'S Manual

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Mitel 6800 Series SIP Phone Release 4.2.0 Administrator Guide
6-10
SIP MESSAGE SEQUENCE FOR BLIND TRANSFER
The SIP message sequence for Blind Transfer avoids the transfer target having two
simultaneous calls. Prior to release 1.4, a CANCEL message was sent to the transfer target
(if it was in a ringing state) after sending a REFER to the transferee to complete the transfer.
In the 1.4 and later releases, the CANCEL is now sent before the REFER message.
The following parameter allows the system administrator to force the phone to use the Blind
Transfer method available in software versions prior to 1.4:
• sip cancel after blind transfer
This parameter is configurable via the configuration files only.
CONFIGURING SIP MESSAGE SEQUENCE FOR BLIND TRANSFER
For the specific parameter you can set in the configuration files for enabling/disabling the blind
transfer method, see Appendix A, the section,
“Blind Transfer Setting” on page A-274.
SIP SETTINGS FOR SEMI-ATTENDED TRANSFERS
SIP MESSAGE SEQUENCE
The SIP message sequence for a Semi-Attended Transfer allows the transferor to start the
transfer while the target phone is still ringing.
The following parameter supports different behaviors of a semi-attended transfer:
• sip refer-to with replaces
This parameter is configurable via the configuration files only.
The combination of this new parameter (
“sip refer-to with replaces”
) and the existing
parameter (
“sip cancel after blind transfer”
) determines how the semi-attended transfer is
completed. The following table shows how the old and new parameters work together:
CONFIGURATION FILES
IF THEN
The “sip cancel after blind transfer” parameter is
set to 0 and the “sip refer-to with replaces”
parameter is set to 0 The phone sends CANCEL before REFER for
semi-attended transfer.
The “sip cancel after blind transfer” parameter is
set to 1 and the “sip refer-to with replaces”
parameter is set to 0 The phone sends CANCEL after REFER for
semi-attended transfer.
The “sip cancel after blind transfer” parameter is
set to 0 and the “sip refer-to with replaces”
parameter is set to 1 The phone sends REFER with Replaces for
semi-attended transfer and NO CANCEL.
The “sip cancel after blind transfer” parameter is
set to 1 and the “sip refer-to with replaces”
parameter is set to 1 The phone sends REFER with Replaces for
semi-attended transfer and NO CANCEL.