Patent ID: 8719930

Claim:
A method of detecting and mitigating network attacks in a Voice-Over-IP (VoIP) network, comprising: receiving, by a server, information related to a mitigation action for a call, the mitigation action being generated by an analyzer based on detecting a possible attack by the call, the information including a complexity level for administering an audio challenge-response test to the call; generating, by the server, a script including variables for identifying a plurality of altered sound files for the audio challenge-response test, the altered sound files including one or more altered digit files and one or more inter-digit noise files, each altered digit file comprising a combination of clear voice sound of a digit and an amount of background noise added according to a signal-to-noise ratio of the complexity level, and each inter-digit noise file providing a variable spacing in the form of noise between the altered digit files; assigning, by the server, a routing label to the call, the routing label including one or more parameters for configuring the variables of the script according to the complexity level; transmitting, by the server, the script and the routing label to the guardian module; defining, by the guardian module, the variables of the script to identify the plurality of altered sound files for the audio challenge-response test, wherein each altered sound file is randomly selected by the guardian module subject to the parameters of the routing label; and administering, by the guardian module, the audio challenge-response test to the call based on the script.