Telecommunication using Optical Communication has become daily toast of life for the past few decades. Its bandwidth usage, cost, performance and reliability has made it highly marketable around the whole world. As these fibre optic cables stretch across the globe and carry information not only to government but also to various banks, hospitals, educational institutes, military etc., its vulnerability to attacks and question on security have increased. The book presented briefly discusses the history of fibre optics, explains the basics of fibre optic technologies, discusses the vulnerabilities in fibre optics and finally proposes two algorithms to protect the fibre optics from intrusion.