Is it possible to block an inbound number (CID) in the Adtran 550? Thank you!
Not really.
If the telco connection is a PRI and the connection to your end equipment is also PRI, you can set it to "Swap ANI/DNIS" so that when the call comes from the Telco, the ATLAS will swap ANI and DNIS, and then route the call based on the ANI, You can configure any port to accept the unwanted ANI. Then the rest of the calls can go out the USER TERM PRI, and you can "Swap ANI/DNIS" again so that the correct DNIS is sent to the end equipment... Of course when doing this, if there is no ANI, then the call won't be routed anywhere and will fail.
Good Luck,
Patrick