The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 21, 1999
Filed:
Dec. 23, 1996
Michael Tessler, Memphis, TN (US);
Pierre Belzile, Lachine, CA;
Charles Meubus, Westmount, Quebec, CA;
Nortel Networks Corporation, Montreal, CA;
Abstract
The present invention relates to a system and a method for limiting call velocity attempts in the public switched telephone network. A central office of the network is provided with a program element that examines all the physical channels from respective customer premises equipments (CPE). The program element counts the number of times each CPE goes off-hook within a given period of time. This condition is interpreted as an attempt to establish a call through the telephone network. If the number of attempts exceeds a threshold, the physical channel is de-activated for a predetermined time period. De-activation means that call establishment over that channel is negated for all possible destinations. This can be implemented by preventing establishment of dial tone. In a variant, selective de-activation is effected. More specifically, the program element in the central office examines the digits dialed at the CPE and authorizes call establishment only when certain specific destinations are attempted to be reached, such as emergency services (9-1-1 calls, for example). For all other destinations call establishment is denied or delayed. The present invention is particularly useful in controlling repetitive dialing that may overload the telephone network.