The Caller ID feature displays calling party information on your display telephone that is signaled over ISDN or H.323 trunks.
For a description about calling party information that is signaled over multifrequency (MF) or Session Initiation Protocol (SIP) trunks to your display telephone, see the Automatic Number Identification feature.
For a description about calling party information that is signaled over Centralized Automatic Message Accounting (CAMA) trunks to your local emergency rapid response organization, see the E911 feature.
Communication Manager stores and displays up to 15 characters of caller ID information, which the central office (CO) sends on incoming calls. If the information is longer than 15 characters, the software truncates the information to 15 characters. If the caller ID information is not received, the system displays the trunk group name and the trunk access code (TAC).
In the US, the CO sends both calling party name and calling party number, if this information is available. In Japan, the CO sends only the calling party number. This information is sent on a CO loop-start trunk in the US. In Japan, this information is sent on either a CO loop-start trunk, a Direct Inward Dialing (DID) trunk, or a Direct Inward and Outward Dialing (DIOD) trunk.
