05206901 is referenced by 211 patents and cites 5 patents.

A system for alerting a plurality of telephones in response to an incoming call to a destination directory number. A handling switch sends a query to a centralized database requesting routing instructions, and the database returns the directory numbers of the plurality of telephones to be alerted for incoming calls to the destination directory number. The busy/idle status of all of the plurality of telephones is checked, and an alerting signal is sent to all idle telephones. The handling switch is notified as to which alerted telephone has an off-hook appearance first, and the incoming call is routed to that telephone.

Title
Method and apparatus for alerting multiple telephones for an incoming call
Application Number
7/812787
Publication Number
5206901
Application Date
December 23, 1991
Publication Date
April 27, 1993
Inventor
George Y Wyatt
Howell
NJ, US
Sankara R Polepalle
Holmdel
NJ, US
Murphy Kolipakam
East Brunswick
NJ, US
John B Harlow
Middletown
NJ, US
Agent
Michael B Johannesen
Assignee
AT&T Bell Laboratories
NJ, US
IPC
H04M 7/00
H04M 3/42
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