Communication system for detecting an unauthorized intruder terminal unit
First Claim
Patent Images
1. Communication system comprising:
- a. a station (2) for charge metering of a connection point (3), which station comprises a monitoring circuit (7) for;
detecting a request for a connection set-up from the connection point (3);
either establishing the absence of a message after a given period of time or evaluating the contents of a message that has arrived from the connection point (3) after the request for a connection set-up has arrived;
rejecting the request for a connection set-up if invalid parameters of the connection point (3) are established; and
b. a terminal unit (1) connected to the connection point (3), said terminal unit being assigned an evaluation circuit (6) which circuit, once it has detected the intrusion of an unauthorized terminal unit at the connection point (3), sends out an error message to the monitoring circuit (7), said monitoring circuit (7) designating the error message as an invalid parameter.
3 Assignments
0 Petitions
Accused Products
Abstract
The invention relates to a communication system comprising a station (2) for charge metering of a connection point. This station comprises a monitoring circuit (7) for detecting a request for a connection set-up from the connection point (3), either for establishing the absence of a message after a given period of time, or for evaluating the contents of a message that has arrived from the connection point (3) after the request for a connection set-up has arrived, and for rejecting the request for a connection set-up if invalid parameters of the connection point (3) are established.
58 Citations
7 Claims
-
1. Communication system comprising:
-
a. a station (2) for charge metering of a connection point (3), which station comprises a monitoring circuit (7) for; detecting a request for a connection set-up from the connection point (3); either establishing the absence of a message after a given period of time or evaluating the contents of a message that has arrived from the connection point (3) after the request for a connection set-up has arrived; rejecting the request for a connection set-up if invalid parameters of the connection point (3) are established; and b. a terminal unit (1) connected to the connection point (3), said terminal unit being assigned an evaluation circuit (6) which circuit, once it has detected the intrusion of an unauthorized terminal unit at the connection point (3), sends out an error message to the monitoring circuit (7), said monitoring circuit (7) designating the error message as an invalid parameter. - View Dependent Claims (2, 3, 4, 5)
-
-
6. Communication system comprising:
-
a. a station (2) for charge metering of a connection point, which station comprises a monitoring circuit (7) for; detecting a request for a connection set-up from the connection point (3); either establishing the absence of a message after a given period of time or evaluating the contents of a message that has arrived from the connection point (3) after the request for a connection set-up has arrived; rejecting the request for a connection set-up if invalid parameters of the connection point (3) are established; and b. a terminal unit (1) connected to the connection point (3) is assigned an evaluation circuit (6) which comprises a first counter (13) for counting metering signals and a first controller (12) for forming a message containing a count of the first counter (13) for the monitoring circuit (7), said monitoring circuit (7) comprising a second counter (22) for counting the metering signals and a second controller (21), which second controller evaluates the message that has arrived from evaluation circuit (6) and designates the count of the first counter (13) as an invalid parameter if the two counts of the two counters differ.
-
-
7. Station (2) for charge metering of a connection point (3), which station comprises a monitoring circuit (7) for:
-
detecting a request for a connection set-up from the connection point (3), either establishing the absence of a message after a given period of time or evaluating the contents of a message that has arrived from the connection point (3) after the request for a connection set-up has arrived, and rejecting the request for a connection set-up if invalid parameters of the connection point (3) are established; one of said invalid parameters comprising an error message sent by an evaluation circuit to the connection point (3) upon the detection of the intrusion of an unauthorized terminal unit at the connection point.
-
Specification