Call Cut-Through Parameters; Tty/Tdd Parameters - AudioCodes Mediant 3000 User Manual

User's Manual
53.11.5.7

Call Cut-Through Parameters

The call cut-through parameters are described in the table below.
Parameter
[DigitalCutThrough]
53.11.5.8

TTY/TDD Parameters

The TTY (telephone typewriter) or telecommunications device for the deaf (TDD) is an
electronic device for text communication via a telephone line for those with impaired
hearing. The TTY/TDD parameters are described in the table below.
Parameter
EMS: TTY Transport Type
[TTYTransportType]
Version 6.6
Call Cut-Through Parameters
Enables PSTN CAS channels/endpoints to receive incoming IP calls even
if the B-channels are in off-hook state.

[0] Disabled (default)

[1] Enabled
When enabled, this feature operates as follows:
A Tel-to-IP call is established (connected) by the device for a B-
1
channel.
The device receives a SIP BYE (i.e., IP side ends the call) and plays a
2
reorder tone to the PSTN side for the duration set by the
CutThroughTimeForReOrderTone parameter. The device releases the
call towards the IP side (sends a SIP 200 OK).
The PSTN side, for whatever reason, remains off-hook.
3
If a new IP call is received for this B-channel after the reorder tone has
4
ended, the device "cuts through" the channel and connects the call
immediately (despite the B-channel being in physical off-hook state)
without playing a ring tone. If an IP call is received while the reorder
tone is played, the device rejects the call.
Notes:

If this parameter is disabled and the PSTN side remains in off-hook
state after the IP call ends the call, the device releases the call after 60
seconds.

A special CAS table can be used to report call status events
(Active/Idle) to the PSTN side during Cut Through mode.

This feature can also be configured in a Tel Profile and therefore,
assigned to specific B-channels that use specific CAS tables.
TTY Parameters
Defines the device's transferring method of TTY signals during a
call.

[0] = (Default) Disable.

[1] = Bypass - entering HBR on TTY tone detection. The HBR
coder is selected by the FaxModemBypassCoderType
parameter. The network packets that are generated and
received during the bypass period are regular voice RTP
packets (per the selected bypass coder), but with a different
RTP payload type (103). You can change this payload type by
using the ModemBypassPayloadType parameter. When TTY
53. Configuration Parameters Reference
Description
Description
765 Mediant 3000