Laser as a communication medium can provide a good substitute for the present day communication systems as the problem of interference faced in case of electromagnetic waves is not there and high deal of secrecy is available. Use of laser in communication systems is the future because of the advantages of the full channel speeds, no communication licenses required at present , compatibility with copper or fiber interfaces and no bridge or router requirements . The laser transmission is very secure because it has a narrow beam (any potential evesdropping will result in an interruption which will alert the personnel. Also it cannot be detected with use of spectrum analyzers and RF meters and hence can be used for diverse applications including financial, medical and military. Lasers can also transmit through glass, however the physical properties of the glass have to be considered.

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