Optical layer multicast: Rationale, building blocks, and challenges

Optical layer multicast refers to the support of point-to-multipoint connections directly at the physical layer by employing passive devices capable of splitting the power of an input signal among several outputs. Optical multicast technology will enable a broad set of applications and will open new directions to network design. In this article we examine the underlying principles and essential components for a practical optical multicast service. We also present a set of key research challenges along with a survey of the literature.