This text provides a comprehensive coverage of the design and modelling of the devices and systems required for optical communication networks. It should be a useful reference text for those engineers implementing and designing such networks and deals with modelling and simulation of optical links at the levels both of devices and of systems. Simulation experiments and results are included, as are details of devices under development in research laboratories. Optical and telecommuntications scientists working in research, and development and design engineers working in the field should find this text to be a useful resource.