1. Field of the Invention
The present invention generally relates to intercepting and monitoring signals of any type in a communications network, and more particularly, to wiretapping signals of any type in a communications network.
2. Background of the Art
Telecommunication service providers are required under the federal and state law to assist law enforcement personnel in conducting court authorized electronic surveillance (or wiretapping) of target telephone numbers. Electronic surveillance of a target telephone number generally requires intercepting and monitoring signals associated with a target telephone number.
There are three known methods for conducting electronic surveillance of a target telephone number. The first method uses an analog bridge tap, which includes a wire extending from a local loop concentrator box that terminates the loop associated with the target telephone number. The wire connects to a listening device from which signals associated with incoming and outgoing calls directed to the target telephone number are monitored by law enforcement personnel. However, because the wire and the listening device introduce a significant amount of noise into the monitored signal, the analog bridge tap is generally detectable, and thus, is not an effective means for covert electronic surveillance.
The second method uses a loop extension to extend the loop associated with the target telephone number from a local concentrator box to another location such as, a covert government safe-house, which may be remote from the concentrator box. The loop extension extends from the local concentrator box to the safe-house and loops back to the controlling switching office for the target telephone number. At the safe-house, law enforcement personnel monitor signals associated with the target telephone number through a listening device. Like an analog bridge tap, the loop extension is also detectable because the loop and the listening device introduce significant amount of noise into the monitored signal. In addition, because the monitored signal has to travel the entire length of the loop extension, the loop extension may reduce the power of the monitored signal, and thus, may degrade the service provided to the target telephone number, increasing the likelihood of detection.
The third method intercepts and monitors signals associated with a target telephone number by using a monitoring port at a controlling switching office. Typically, law enforcement personnel use a listening device to monitor the intercepted signals at the controlling switching office or from a remote listening post. This method, however, has the disadvantage that the law enforcement personnel may not be able to exercise control over the controlling switching office during the entire duration of a surveillance, requiring the personnel at the controlling switching office to become a de facto agent of the law enforcement personnel.
Thus, it is desirable to have a method and system for monitoring and intercepting signals of any type in a network without the above-mentioned and other disadvantages of the prior art.
Methods and systems consistent with the present invention intercept and monitor signals of any type in a communications network such that the interception and the monitoring are undetectable. Such methods and systems may intercept and monitor a signal based on one or more items of information such as, a target telephone number, a credit card number, a virtual private network number (VPN), personal identification number (PIN), a prepaid card number, or a third party billing number associated with the signal.
Such methods and systems configure a communications network by provisioning a route to a collection node in the network, defining a first trigger for intercepting a signal associated with a target telephone number, and by defining a second trigger for routing the intercepted signal on the provisioned route to the collection node. The methods and systems then monitor the signal at the collection node by intercepting the signal based on the first trigger and routing the intercepted signal to the collection node based on the second trigger.
In one embodiment, such methods and systems provision a route between one or more switching nodes and a collection node in a communications network, define in the switching nodes a first set of triggers for detecting the signals, and define in a signaling node a second set of triggers for routing the detected signals on the provisioned route to the collection node. The communications network may be any type of network such as, a telecommunications network, a data network (e.g., Transmission Control Protocol/Internet Protocol) capable of supporting voice over Internet Protocol (IP), etc.
When a switching node detects a signal associated with a target telephone number, the switching node identifies a first predefined trigger associated with the target telephone number. The switching node executes the first predefined trigger, which identifies a call treatment tag for routing the detected signal. The switching node then sends via out-of-band signaling or in-band signaling the identified call treatment tag to the signaling node.
Based on the identified call treatment tag, the signaling node identifies a second predefined trigger. The signaling node then executes the second predefined trigger, which routes the detected signal on the provisioned route to the next switching node. Accordingly, for each call treatment tag that the signaling node receives, it executes a corresponding second predefined trigger, which routes the signal on the provisioned route to the next switching node.
After the signaling node routes the signal on the provisioned route to the collection node, the signaling node performs normal call routing steps to route the signal to a destination node. When the setup phase for the signal is completed, law enforcement personnel may monitor the contents of the signal at the collection node. When the detected signal terminates, the switching nodes and the signaling node perform normal call termination steps.
In another embodiment, methods and systems consistent with the present invention intercept and monitor signals of any type in a communications network by provisioning in a switching node a virtual loopback route that links an incoming port to a monitoring port in the switching node, defining in the switching node a first trigger for detecting the signals, and defining in a signaling node a second trigger for routing the detected signals through the provisioned route to a destination node in the network.
When the switching node detects a signal associated with a target telephone number, the switching node identifies the first predefined trigger associated with the target telephone number. The switching node executes the first predefined trigger, which identifies a call treatment tag for routing the detected signal. The switching node then sends via out-of-band signaling or in-band signaling the identified call treatment tag to the signaling node.
Based on the identified call treatment tag, the signaling node identifies a second predefined trigger. The signaling node then executes the second predefined trigger, which routes the detected signal on the virtual loopback route to the monitoring port.
After the signaling node routes the signal on the virtual loopback route to the monitoring port, the signaling node performs normal call routing steps to route the signal to a destination node. When the setup phase of the signal is completed, law enforcement personnel may monitor the contents of the signal at the monitoring port. When the detected signal terminates, the switching nodes and the signaling node perform normal call termination steps.