An ISDN Cause code consists of 2 bytes; the first byte contains the 'location' code (with some other information) and the second byte contains the diagnostic code.
The Location field shows who issued the diagnostic code. This is particularly useful information where the two communicating devices are on different ISDN networks (perhaps with one or more transit networks between), or are using ISDN though a 'private network' such as a PABX.
The possible location codes are:
Location | Value | Meaning |
80 | ||
81 | ||
82 | ||
83 | ||
84 | ||
85 | ||
87 | ||
8A |
