Telephone call security system
First Claim
Patent Images
1. A telephone call security system, comprising:
- a telephone including tone generation means for generating and transmitting tones representative of a telephone identification serial number when a telephone call is placed from the telephone; and
a control switch device including means for permitting access from said telephone to a restricted access carrier, means for receiving said tones representative of a telephone identification serial number, and identification verification means verifying whether said identification number corresponds to the identification of a telephone from which access to the carrier is permitted;
wherein said control switch device further includes coded signal generation means for generating and transmitting to said telephone a coded sequence of tones subsequent to verification of said identification number, means for receiving from said telephone a reply in which said tones are modified in respect to said coded sequence of tones, and means for verifying whether said reply sequence of tones is valid.
1 Assignment
0 Petitions
Accused Products
Abstract
A telephone call security system uses a long distance carrier access switch to prevent unauthorized access to the carrier by causing the switch control system to request a telephone identification serial number from the telephone and deny access if the serial number is not valid or if the number dialed is not an authorized number for the telephone whose serial number has been received. In addition, the system uses a coded query/response dialogue between the telephone and the switch control system for added security. The system may be implemented by modifying the carrier access switch control software and also includes a unique telephone and telephone resident control software.
57 Citations
45 Claims
-
1. A telephone call security system, comprising:
-
a telephone including tone generation means for generating and transmitting tones representative of a telephone identification serial number when a telephone call is placed from the telephone; and a control switch device including means for permitting access from said telephone to a restricted access carrier, means for receiving said tones representative of a telephone identification serial number, and identification verification means verifying whether said identification number corresponds to the identification of a telephone from which access to the carrier is permitted; wherein said control switch device further includes coded signal generation means for generating and transmitting to said telephone a coded sequence of tones subsequent to verification of said identification number, means for receiving from said telephone a reply in which said tones are modified in respect to said coded sequence of tones, and means for verifying whether said reply sequence of tones is valid. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. A telephone call security system, comprising:
-
a control switch device including means for permitting access from a telephone to a restricted access carrier and means for generating and transmitting a coded sequence of tones; a telephone including means for receiving said coded sequence of tones, generating a reply sequence of tones derived from but different than the coded sequence of tones, and transmitting said reply sequence of tones to said control switch device, said control switch device further including means for receiving said reply sequence of tones and determining whether said reply sequence of tones is a valid reply sequence of tones. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28, 29)
-
-
30. A telephone call security system control switch device, comprising
means for receiving a signal representative of a telephone identification number from a telephone; -
means for verifying whether said telephone identification number is valid; coded signal generating means for generating and transmitting to said telephone a coded sequence of tones subsequent to verification of whether said telephone identification number is valid; means for verifying whether a reply sequence of tones received from said telephone in reply to said coded sequence of tones, said reply sequence of tones being different from said coded sequence of tones, is valid; and means for routing a call from a telephone to a restricted access carrier upon verification that said identification number and said reply sequence of tones are both valid. - View Dependent Claims (31, 32, 33, 34, 35, 36, 37, 38, 39)
-
-
40. A telephone, comprising:
-
means in said telephone for generating and transmitting signals from said telephone to a control switch device representative of an identification number of the telephone; means for receiving and decoding a coded sequence of tones received from said control switch device after said identification number of the telephone has been generated and transmitted; means for deriving from the decoded coded sequence of tones a reply sequence of tones which is different from the coded sequence of tones; and means for transmitting said reply sequence of tones to a control switch device in order to obtain access to a long distance carrier. - View Dependent Claims (41, 42, 43)
-
-
44. A method of preventing unauthorized access to a restricted access carrier, comprising the steps of:
-
transmitting a telephone identification serial number from a telephone to an access switch which controls access to the carrier; transmitting a coded sequence of tones from the access switch to the telephone and permitting access to the carrier only if the telephone generates and returns a valid reply sequence of tones derived from but different than said coded sequence of tones and only if the serial number is that of an authorized telephone.
-
-
45. A method of preventing unauthorized access to a restricted access carrier, comprising the steps of:
-
transmitting a coded signal including a coded sequence of tones from a carrier access switch to a telephone; and permitting access to the carrier only if the telephone generates and returns a valid reply signal including a second sequence of tones which are modified in respect to the coded sequence of tones received from the carrier access switch.
-
Specification