Optical switch fabrics for ultra High Capacity IP routers

Next-generation IP, ATM, and MPLS routers will rely on optical switch fabrics to overcome cost, power, space and scalability problems that arise in growing traditional electrical backplanes into the terabit regime. In this paper we present and discuss several switch fabrics that employ different optical technologies. We describe a promising approach based on arrayed waveguide gratings and fast wavelength tuning and explain the challenges that arise in making this method technically and commercially viable. Finally, we demonstrate an optical switch fabric capable of 1.2 Tb/s throughput and show error-free packet switching with four ports running at 40 Gb/s each.