Automatic Intercept Service
W. A. Winckelmann · IEEE Transactions on Communication Technology · 1967
The automatic intercept system described in this paper will route telephone calls for nonworking numbers to a centralized time division switch which connects the calling customer to a series of prerecorded announcements. The customer is told what number he has reached, the status of that number, and if available, the new number at which the called party may be reached.