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Advances in optical switching and networking: past, present, and future

In this paper a survey of optical networks and switching is presented. It starts with a discussion of the development of telecommunication industry, tracing the great shift from asynchronous, to synchronous (SONET), to optical networks. It also presents the main drivers that led to today's high-speed networks. Some of the main technologies of optical networks such as wavelength division multiplexers (WDM), dense wavelength division multiplexers (DWDM), and erbium doped fiber amplifiers (EDFA). Then, we shift our focus to optical switching starting from optical-electrical-optical (OEO) switches to the all-optical/photonic switches. Great emphasis is directed towards the later, including its promise for optical networks, its characteristics, as well as the recent development in photonic switching technologies (MEMS, liquid crystals, bubbles, thermo optics and more). Finally, the challenges facing its large deployment in today's networks are surveyed.