9 ELECTRONIC AND OPTICAL COMPONENTS, NAMELY, CONNECTOR, ADAPTOR, PATCH CORD, COUPLER, FILTER, ISOLATOR, WAVELENGTH DIVISION MULTIPLEXOR, ATTENUATOR, COLLIMATOR, VARIABLE OPTICAL ATTENUATOR, CIRCULATOR, PATCH PANEL, DENSE WAVELENGTH DIVISION MULTIPLEXOR, CABLE CLOSURE, OPTICAL SWITCH, AND OPTICAL AMPLIFIER