Requirements, architectures, and technologies for optical cross-connects

The growing demands for telecommunications bandwidth, and the development of high-capacity optical networks, are creating a demand for large-port-count optical cross-connects. The initial cross-connect products currently being offered all utilize electronic switch fabrics, and while they are meeting the immediate needs for network operators, there is a growing consensus that transparent optical switch fabrics will be needed in the near future. The purpose of the paper is to review the requirements and architectures for optical switch fabrics, and to compare and evaluate the various optical switch technologies that are available to implement fabrics capable of meeting those requirements.