Treat either condition as a suspicious incident. Inspection of Telephone Wiring. Wiring associated with the telephones under test are inspected for attachments, and damage. Damaged wiring is often the only evidence of a prior wiretap. Inspection of Junction Blocks.
Junction blocks are where telephone wires connect to each other in the building.
These connected wires form a path between the telephone instrument and the on-premises, telephone switching equipment. Junction blocks are an easy, and relatively safe, place to attach a wiretap device. This type of common attack is called a direct, or bridge, tap. Telephone Room Inspection. This is another area of vulnerability which requires an inspection from both a wiretapping and physical security point of view.