Optical paths and realization technologies

This paper explores the transport technologies that will enable a further leap forward in transport network evolution. It is demonstrated that optical path technologies such as WP (wavelength path) and VWP (virtual wavelength path) enhance not only the transmission capacity, but also cross-connect node throughput cost-effectively by capitalizing on the wavelength routing scheme. This results in significant transport network cost reduction. Optical path realization technologies focusing on optical path cross-connect systems are examined. Requirements for the optical path cross-connect system are elucidated and a new cross-connect system architecture is proposed. The architecture exploits PLC (planar lightwave circuit) and other commercially available technologies suitable for mass-production. It is proved that the architecture has various advantages such as highly modular-growth capability, low optical loss, and the maximum commonality for WP and VWP. The optical path technologies introduced in this paper will pave the way for a new transport network paradigm, a ubiquitous, bandwidth-abundant and affordable broadband ISDN.