ISUP CRCS Configuration Bytes (ITU)

Bytes 1–5 define the format of the COT message. These should not be changed.

Byte | Description | Value
--- | --- | ---
0x01 | Information Length | 0x04
0x02 | Message ID | 0x05 (COT)
0x03 | Parameter Count | 0x01
0x04 | Parameter1 ID | 0x10 (Continuity Indicator)
0x05 | Parameter 1 Data Length | 0x00
0x06–0x09 | Not Used |
0x0A | Continuity Recheck | 0x00=Enables unlimited repeated continuity checks 0x01= Limits the repeated continuity checks to n+2 times where N is the value of config byte 0x0B. (default)
0x0B | Number of times to recheck | 2 (default)

Release (REL) when COT successful
0x14 | Information Length | 0x06
0x15 | Message ID | 0x0C (REL)
0x16 | Number of Parameters | 0x01
0x17 | Parameter 1 Data Type | 0x12 (Cause Indicators)
0x18 | Parameter 1 Data Length | 0x02 (Cause Indicators)
0x19 | Parameter 1 Data[0] | 0x80 (Location=User)
0x1A | Parameter 1 Data[1] | 0x90 (Cause 16=Normal Call Clearing)

Release (REL) if RLC is not received
0x1E | Information Length | 0x06
0x1F | Message ID | 0x0C (REL)
0x20 | Number of Parameters | 0x01
0x21 | Parameter 1 Data Type | 0x12 (Cause Indicators)
0x22 | Parameter 1 Data Length | 0x02 (Cause Indicators)
0x23 | Parameter 2 Data [0] | 0x80 (Location=User)
0x24 | Parameter 1 Data[1] | 0xE6 (Cause 102; Recovery on timer expiry)