Technical information

DEFINITY ECS, DEFINITY Communications Systems,
System 75, and System 85
Issue 7 June 2001
6-23
Enhanced Call Transfer
With Enhanced Call Transfer, the voice mail system uses a digital control link
message to initiate the transfer and the switch verifies that the requested
destination is a valid station in the dial plan. With Enhanced Call Transfer, when
voice mail system callers enter *T followed by digits (or *A for name addressing)
and #, the following actions take place:
1. The voice mail system verifies that the digits entered contain the same
number of digits as administered for extension lengths. If call transfer is
restricted to subscribers (for the DEFINITY AUDIX System and the Avaya
I
NTUITY System only), the voice mail system also verifies that the digits
entered match the extension number of an administered subscriber.
NOTE:
When callers request a name addressing transfer, the name must
match the name of an AUDIX, DEFINITY AUDIX, or Avaya I
NTUITY
Voice Mail System subscriber (either local or remote) whose
extension number is in the dial plan.
2. If Step 1 is successful, the voice mail system sends a transfer control link
message containing the digits to the switch. If Step 1 is unsuccessful, the
voice mail system plays an error message to the caller and prompts for
another try.
3. The switch verifies that the digits entered match a valid station number in
the dial plan.
 If Step 3 is successful, the switch completes the transfer,
disconnects the voice mail system voice port, and sends a
“successful transfer” control link message to the voice mail system.
 If Step 3 is unsuccessful, the switch leaves the voice mail system
voice port connected to the call, sends a “fail” control link message
to the voice mail system, and then the voice mail system plays an
error message requesting another try.
With Enhanced Call Transfer, the reason for a transfer is included in the control
link message that the voice mail system sends to the switch. For Call Answer
calls, such as calls that are redirected to the voice mail system when an extension
is busy or does not answer, when a caller enters 0 to Escape to Attendant, the
voice mail system normally reports the transfer to the switch as “redirected.”
The switch uses this reason to determine how to proceed with the call. If the
reason for the transfer is “redirected,” the call will not follow the destination’s
coverage path or its call forwarding path. This is because the switch will not
redirect a previously redirected call.