One countermeasure is encryption, to make the stolen data unintelligible to the thief. Another is to deploy a fiber-optic sensor into the existing raceway, conduit or armored cable. In this scenario, anyone attempting to physically access the data (copper or fiber infrastructure) is detected. A small number of alarm systems manufacturers provide a simple way to monitor the optical fiber for physical intrusion. There is also a proven solution that utilizes existing unused fiber (dark fiber) in a multi-strand cable for the purpose of creating an alarm system.