Automatic Number Identification – A telephone network feature that passes the number of the phone the caller is using to the call center, real-time. ANI may arrive over the D channel of an ISDN PRI circuit (out-of-band signaling), or before the first ring on a single line (inband signaling). ANI is delivered from long distance companies. Caller ID is the local phone company version of ANI, and is delivered inband. ANI is a North American term, and Calling Line Identification (CLI) is an alternative term used elsewhere.