| Setup
of an ISDN call using Q.931 |
| Setup |
|
|
|
| off- |
||
| hook |
||
| Setup |
| Call
proceed |
|
|
|
| SS7 |
||
| ISUP |
||
| Alert |
| “ring” |
| Alert |
| Connect |
|
|
|
| user B |
||
| answers |
||
| Connect |
| connection ok |