System and method for limiting call velocity attempts in a public switched telephone network

摘要

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.