Bob has heard about weaknesses related to phone systems from one of his phreaker friends. His friend warns him about the potential danger of listening devices that are sometimes badly configured.Bob…

Bob has heard about weaknesses related to phone systems from one of his phreaker friends. His friend warns him about the potential danger of listening devices that are sometimes badly configured.Bob is interested in being proactive and he would like to perform a validation of his company phone number range to see if there are any listening devices that might be used by a malicious attacker to get access to the internal network.What category of tool would Bob use for this purpose?