AudioCodes Mediant 500 E-SBC, User Manual

Page: 849 / 920

User's Manual 54. Configuration Parameters Reference
Version 6.8 849 Mediant 500 E-SBC
Parameter Description
IP side.

[5] = IP-to-Tel Blind Transfer mode supported for ISDN (PRI)
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
received, the device initiates a transfer by sending a Facility
message to the PBX.

Tel-to-IP (network side): When a Facility message initiating
an out-of-band blind transfer is received from the PBX, the
device sends a SIP REFER message to the IP side (if the
EnableNetworkISDNTransfer parameter is set to 1).
Note: For configuring trunk transfer mode per trunk, use the
parameter TrunkTransferMode_x.
[TrunkTransferMode_x] Determines the trunk transfer mode per trunk (where x denotes the
Trunk number). For configuring trunk transfer mode for all trunks
and for a description of the parameter options, refer to the
parameter TrunkTransferMode.
[EnableTransferAcrossTrunk
Groups] Determines whether the device allows ISDN ECT, RLT or TBCT IP-
to-Tel call transfers between B-channels of different Trunk Groups.

[0] = (Default) Disable - ISDN call transfer is only between B-
channels of the same Trunk Group.

[1] = Enable - the device performs ISDN transfer between any
two PSTN calls (between any Trunk Group) handled by the
device.
Note: The ISDN transfer also requires that you configure the
parameter TrunkTransferMode_x to 2.
Web: ISDN Transfer
Capabilities
EMS: Transfer Capability To
ISDN
CLI: isdn-xfer-cab Defines the IP-to-ISDN Transfer Capability of the Bearer Capability
IE in ISDN Setup messages, per trunk.

[-1] Not Configured

[0] Audio 3.1 (default)