Consultation Feature; Call Transfer; Consultation Call Transfer - AudioCodes Mediant 800B MSBR User Manual

30.4

Consultation Feature

The device's Consultation feature allows you to place one number on hold and make a
second call to another party.

After holding a call (by pressing hook-flash), the holding party hears a dial tone and
can then initiate a new call, which is called a Consultation call.

While hearing a dial tone, or when dialing to the new destination (before dialing is
complete), the user can retrieve the held call by pressing hook-flash.

The held call can't be retrieved while ringback tone is heard.

After the Consultation call is connected, the user can toggle between the held and
active call by pressing the hook-flash key.
Note: The Consultation feature is applicable only to FXS interfaces.
30.5

Call Transfer

This section describes the device's support for call transfer types.

30.5.1 Consultation Call Transfer

The device supports Consultation Call Transfer using the SIP REFER message and
Replaces header. The common method to perform a consultation transfer is described in
the following example, which assumes three call parties:

Party A = transferring

Party B = transferred

Party C = transferred to
1. A Calls B.
2. B answers.
3. A presses the hook-flash button and places B on-hold (party B hears a hold tone).
4. A dials C.
5. After A completes dialing C, A can perform the transfer by on-hooking the A phone.
6. After the transfer is complete, B and C parties are engaged in a call.
The transfer can be initiated at any of the following stages of the call between A and C:

Just after completing dialing C phone number - transfer from setup

While hearing ringback – transfer from alert

While speaking to C - transfer from active
Note: For FXS interfaces, the device can also handle call transfers using SIP INVITE
and re-INVITE messages, instead of REFER messages. This is useful when
communicating with SIP UAs that do not support the receipt of REFER messages.
This feature is applicable to FXS interfaces. To enable this support, use the
EnableCallTransferUsingReinvites parameter.
The device also supports attended (consultation) call transfer for BRI phones (user side)
connected to the device and using the Euro ISDN protocol. BRI call transfer is according to
User's Manual 430
Mediant 800B MSBR
Document #: LTRT-12813