Querying Device Channel Resources Using Sip Options - AudioCodes Mediant 2000 User Manual

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
Max-Forwards: 70
From: "anonymous" <sip:anonymous@anonymous.invalid>;tag=1c25298
To: <sip:101@10.33.2.53;user=phone>
Call-ID: 11923@10.33.2.53
CSeq: 1 INVITE
Contact: <sip:100@10.33.2.53>
X- Detect: Request=CPT,FAX
SIP/2.0 200 OK
Via: SIP/2.0/UDP 10.33.2.53;branch=z9hG4bKac5906
From: "anonymous" <sip:anonymous@anonymous.invalid>;tag=1c25298
To: <sip:101@10.33.2.53;user=phone>;tag=1c19282
Call-ID: 11923@10.33.2.53
CSeq: 1 INVITE
Contact: <sip:101@10.33.2.53>
X- Detect: Response=CPT,FAX
INFO sip:101@10.33.2.53;user=phone SIP/2.0
Via: SIP/2.0/UDP 10.33.2.53;branch=z9hG4bKac5906
Max-Forwards: 70
From: "anonymous" <sip:anonymous@anonymous.invalid>;tag=1c25298
To: <sip:101@10.33.2.53;user=phone>
Call-ID: 11923@10.33.2.53
CSeq: 1 INVITE
Contact: <sip:100@10.33.2.53>
X- Detect: Response=CPT,FAX
Content-Type: Application/X-Detect
Content-Length: xxx
Type = CPT
Subtype = SIT
28.3 Querying Device Channel Resources using SIP
OPTIONS
The device reports its maximum and available channel resources in SIP 200 OK responses
upon receipt of SIP OPTIONS messages. The device sends this information in the SIP X-
Resources header with the following parameters:

telchs: specifies the total telephone channels as well as the number of free (available)
telephone channels

mediachs: not applicable
Below is an example of the X-Resources:
X-Resources: telchs= 140/100;mediachs=0/0
In the example above, "telchs" specifies the number of available channels and the number
of occupied channels (100 channels are occupied and 140 channels are available).
SIP User's Manual 402
Mediant 2000
Document #: LTRT-68814