Telephone switch for public telephone network uses personalised lists on wrong number server to require call confirmation for often confused numbers can include automatic approved list generation

摘要

A telephone switch (C1, CAS1, SS) calls a terminal (TUS) on request from another terminal (T2) only if its number (N2) is included in a personalised approved list (LUS) and makes a call confirmation (RQC) request to the calling terminal if it does not. Includes Independent claims for user entry of numbers on the approved list or automatic entry based on the frequency of calls, calls from the protected terminal or length of calls