(12) United States Patent ao) Patent No.: us 6,567,194 Bi
Badr (45) Date of Patent: May 20,2003
Demeester, Piet, Resilience in WDM networks, All Optical Network Conference, organized by Vision in Business, London, Jun. 1998.
* cited by examiner
Primary Examiner—-Thomas Mullen (57) ABSTRACT
Optical systems of the present invention are configured in optical networks including a plurality of optical switch nodes interconnected by a plurality of optical transmission fibers, or other waveguides. The transmission fibers in the network can provide working and/or protection capacity for information, or communications traffic, being transmitted through the network. In various embodiments of the network, multiple diverse, working routes are provided on a single fiber path interconnecting a plurality of switch nodes. The multiple, diverse working routes can then be protected using a common protection fiber or path to provide shared protection. The switch nodes include optical switch configured to provide various levels of optical switching depending upon the network configuration. For example, line switches as well as optical cross-connects and routers can be deployed in the present invention to switch one or more wavelengths between the working and protection fibers. The optical systems can be further configured to carry lower priority traffic on the protection fibers or wavelengths during normal operation to increase the overall normal operating capacity of the system.
14 Claims, 3 Drawing Sheets