This paper deals with the twin concepts of optical networking and dense wavelength division multiplexing. The paper talks about the various optical network architectures and the various components of an all-optical network like Optical Amplifiers, Optical Add/Drop Multiplexers, Optical Splitters etc. Important optical networking concepts like wavelength routing and wavelength conversion are explained in detail. Finally this paper deals with industry related issues like the gap between research and the industry, current and projected market for optical networking & DWDM equipment and future direction of research in this field. Optical networking using DWDM offers a new approach that helps enterprises and network provides to realize the huge potential of high bandwidth networking. It overcomes the constraints imposed by current server and campus network architectures to interconnect LANs and SANs over full optical backbone provides a cost effective migration path for enterprise to unleash the power of their server and networking recourses.