AudioCodes Mediant 1000B User Manual page 672

The device can map these SIT tones to a Q.850 cause and then map them to SIP 5xx/4xx
responses,
SITQ850CauseForIC, SITQ850CauseForVC, and SITQ850CauseForRO.
Table 44-7: Special Information Tones (SITs) Reported by the device
Special Description
Information
Tones (SITs)
Name
NC1 No circuit found
IC Operator intercept
VC Vacant circuit (non
registered number)
Reorder (system
RO1
busy)
NC* -
RO* -
IO* -
For example:
INFO sip:5001@10.33.2.36 SIP/2.0
Via: SIP/2.0/UDP 10.33.45.65;branch=z9hG4bKac2042168670
Max-Forwards: 70
From: <sip:5000@10.33.45.65;user=phone>;tag=1c1915542705
To: <sip:5001@10.33.2.36;user=phone>;tag=WQJNIDDPCOKAPIDSCOTG
Call-ID: AIFHPETLLMVVFWPDXUHD@10.33.2.36
CSeq: 1 INFO
Contact: <sip:2206@10.33.45.65>
Supported: em,timer,replaces,path,resource-priority
Content-Type: application/x-detect
Content-Length: 28
Type= CPT
SubType= SIT-IC
The X-Detect event notification process is as follows:
1. For IP-to-Tel or Tel-to-IP calls, the device receives a SIP request message (using the
X-Detect header) that the remote party wishes to detect events on the media stream.
For incoming (IP-to-Tel) calls, the request must be indicated in the initial INVITE and
responded to either in the 183 response (for early dialogs) or in the 200 OK response
(for confirmed dialogs).
2. Once the device receives such a request, it sends a SIP response message (using the
X-Detect header) to the remote party, listing all supported events that can be detected.
The absence of the X-Detect header indicates that no detections are available.
3. Each time the device detects a supported event, the event is notified to the remote
party by sending an INFO message with the following message body:
•
Content-Type: application/X-DETECT
•
Type = [AMD | CPT | FAX | PTT...]
•
Subtype = xxx (according to the defined subtypes of each type)
Below is an example of SIP messages using the X-Detect header:
INVITE sip:101@10.33.2.53;user=phone SIP/2.0
Via: SIP/2.0/UDP 10.33.2.53;branch=z9hG4bKac5906
User's Manual
using the parameters
First Tone
Frequency
Duration
(Hz)
985.2
913.8
985.2
913.8
913.8
985.2
913.8
672
Mediant 1000B Gateway & SBC
SITQ850Cause,
Second Tone
Frequency
Duration
(ms) (Hz) (ms)
380 1428.5 380
274 1370.6 274
380 1370.6 274
274 1428.5 380
380 1370.6 380
274 1370.6 380
380 1428.5 274
Document #: LTRT-27034
SITQ850CauseForNC,
Third Tone
Frequency
Duration
(Hz) (ms)
1776.7 380
1776.7 380
1776.7 380
1776.7 380
1776.7 380
1776.7 380
1776.7 380