AudioCodes Mediant 500L User Manual page 205

User's Manual
be left. For more information on AMD, see ''Answering Machine Detection (AMD)'' on
page 210.

Call Progress Tone (CPT): Detects whether a specific tone, defined in the installed
CPT file is received from the call. It can be used to detect the beep sound played by
an answering machine (as mentioned above), Special Information Tones (SIT) which
indicate call failure with a recorded announcement describing the call failure, and the
busy, reorder and ring tones.

Fax/modem machine: Detects whether a fax has answered the call (preamble, CED,
CNG, and modem).

PTT: Detects the start and end of voice.
Note:
•
Currently, PTT is supported only for Gateway calls.
•
Fax and SIT event detection is applicable only to Gateway calls.
•
Event detection on SBC calls is supported only for calls using the G.711 coder.
The X-Detect header is used for event detection as follows:

X-Detect header in the INVITE message received from the application server
requesting a specific event detection:
X-Detect: Request=[event type to detect]

X-Detect header in the SIP response message -- SIP 183 (for early dialogs) or 200 OK
(for confirmed dialogs) -- sent by the device to the application server specifying which
of the requested events it can detect (absence of the X-Detect header indicates that
the device cannot detect any of the events):
X-Detect: Response=[supported event types]

Each time the device detects the supported event, it sends an INFO message to the
remote party with the following message body:
Content-Type: Application/X-Detect
Type = [event type]
Subtype = [subtype of each event type]
The table below lists the event types and subtypes that can be detected by the device. The
text shown in the table are the strings used in the X-Detect header. The table also provides
a summary of the required configuration. For SBC calls, event detection is enabled using
the IPProfile_SBCHandleXDetect parameter in the IP Profiles table (see Configuring IP
Profiles on page 438).
Event
Type

Voice (live voice)
AMD

Automata (answering machine)

Silence (no voice)

Unknown

Beep (greeting message of
answering machine)

SIT-NC
CPT

SIT-IC

SIT-VC
Version 7.2
Table 14-1: Supported X-Detect Event Types
Subtype Description and Required Configuration
Event detection using the AMD feature. For more
information, see Answering Machine Detection
(AMD) on page 210.
Event detection of tones using the CPT file.
Create a CPT file with the required tone types of
1
the events that you want to detect.
205 Mediant 500L Gateway & E-SBC
14. Media