Theoretical demonstration of light injection into the communication fibre

With the rapid development of the technology of optical communication, the security in it has attracted more and more people´s attention and even has become a critical component of national security. Compared with the traditional telecommunication, optical communication is regarded as a kind of secure communication because optical fiber, transmission medium of it, is immune to the typical issues of electromagnetic interference (EMI)/radio-frequency interference (RFI). However, the essential characteristics of the optical fiber make it vulnerable to a variety of attacks, including physical infrastructure attacks, eavesdropping, interception, and jamming. In this paper, we proposed a new model to inject the light into a communication fiber without damaging the cladding or core of it. From numberical calculation, the power of injected optical signal can reach to more than 20% of the input power. This level of injected signal is sufficient to interfere with the signal transported in the communication. So measures to combat this kind of inference and deception should be taken.