AudioCodes Mediant 800B User Manual page 1159

User's Manual
Parameter
Version 7.2
Facility messages) to perform the transfer.
Note:

For RLT ISDN transfer, the parameter
SendISDNTransferOnConnect must be set to 1.

The parameter SendISDNTransferOnConnect can be used to
define if the TBCT/ECT transfer is performed after receipt of
Alerting or Connect messages. For RLT, the transfer is always
done after receipt of Connect (SendISDNTransferOnConnect
is set to 1).

This transfer can be performed between B-channels from
different trunks or Trunk Groups, by using the parameter
EnableTransferAcrossTrunkGroups.

The device initiates the ECT process after receiving a SIP
REFER message only for trunks that are configured to User
side.

[3] = Supports CAS Normal transfer. When a SIP REFER
message is received, the device performs a Blind Transfer by
executing a CAS Wink, dialing the Refer-to number to the switch,
and then releasing the call.

[4] = Supports QSIG Single Step transfer PRI/BRI:

IP-to-Tel: When a SIP REFER message is received, the
device performs a transfer by sending a Facility message to
the PBX, initiating Single Step transfer. Once a success return
result is received, the transfer is completed.

Tel-to-IP: When a Facility message initiating Single Step
transfer is received from the PBX, a SIP REFER message is
sent to the IP side.

[5] = IP-to-Tel Blind Transfer mode supported for ISDN PRI/BRI
protocols and implemented according to AT&T Toll Free Transfer
Connect Service (TR 50075) "Courtesy Transfer-Human-No
Data". When the device receives a SIP REFER message, it
performs a blind transfer by first dialing the DTMF digits (transfer
prefix) defined by the parameter XferPrefixIP2Tel (configured to
"*8" for AT&T service), and then (after 500 msec) the device dials
the DTMF of the number (referred) from the Refer-To header
sip:URI userpart.
If the hostpart of the Refer-To sip:URI contains the device's IP
address, and if the Trunk Group selected according to the IP to
Tel Routing table is the same Trunk Group as the original call,
then the device performs the in-band DTMF transfer; otherwise,
the device sends the INVITE according to regular transfer rules.
After completing the in-band transfer, the device waits for the
ISDN Disconnect message. If the Disconnect message is received
during the first 5 seconds, the device sends a SIP NOTIFY with
200 OK message; otherwise, the device sends a NOTIFY with 4xx
message.

[6] = Supports AT&T toll free out-of-band blind transfer for trunks
configured with the 4ESS ISDN protocol. AT&T courtesy transfer
is a supplementary service which enables a user (e.g., user "A") to
transform an established call between it and user "B" into a new
call between users "B" and "C", whereby user "A" does not have a
call established with user "C" prior to call transfer. The device
handles this feature as follows:

IP-to-Tel (user side): When a SIP REFER message is
1159
67. Configuration Parameters Reference
Description
Mediant 800B Gateway & E-SBC