Why does my Cisco IP Phone display “From 9” when I receive a call from the Public Switched Telephone Network (PSTN)?
A. “From 9” can display if you use an H.323 gateway in order to connect to the PSTN and no calling party information is passed. This can occur in this situation: If the incoming call has no calling party information, the router uses the destination pattern of the first plain old telephone service (POTS) dial peer that is associated with the voice port. If you have a POTS dial peer with a destination pattern of 9T, the incoming call picks up the 9 and presents it as the calling party number. If you cannot enable caller ID, you can prevent this behavior if you complete these steps: • Remove all the POTS dial peers that point to that voice port. • Make a new POTS dial peer with: • destination-pattern . (Note: There is a dot [.] after the destination-pattern.) • direct-inward-dial • the port number (An example is port 1/1/1.) • Paste back all the other POTS dial peers that you had. A. The phone displays “From Unknown Number” rather than “From 9”.
