Abstract: A method and system to economically monitor an optical OOK signal that can detect perceptible changes in signal quality and identify the type of optical impairment causing the change. The invention requires a new and novel combination of known techniques to create an eye diagram of the transmitted pulse in a wavelength division multiplexing systems and then removing the noise from the eye diagram. Economy of operation is achieve by using asynchronous sampling techniques for generating the eye diagram. The resulting “cleaner” eye diagram is then analyzed to identify any changes in performance. In the preferred embodiment, the analysis is conducted on histograms generated from eye diagram, the histograms are computed at a number of points across the optical signal pulse period.

Abstract: A method and system to economically monitor an optical OOK signal that can detect perceptible changes in signal quality and identify the type of optical impairment causing the change. The invention requires a new and novel combination of known techniques to create an eye diagram of the transmitted pulse in a wavelength division multiplexing systems and then removing the noise from the eye diagram. Economy of operation is achieve by using asynchronous sampling techniques for generating the eye diagram. The resulting “cleaner” eye diagram is then analyzed to identify any changes in performance. In the preferred embodiment, the analysis is conducted on histograms generated from eye diagram, the histograms are computed at a number of points across the optical signal pulse period.

Abstract: In a telecommunication network, each node is provided with the same physical topology information relating to a physical construction of telecommunication paths included in the telecommunication network and with the same logical topology information relating to routing of telecommunication paths. When a failure occurs, restoration is effected by transmitting information relating to the failure that has occurred in the telecommunication network, throughout the network. Each node that receives the information relating to the failure determines alternative paths for bypassing the failure using the information relating to the failure, the physical topology information, and the logical topology information. Then service is switched to the alternative paths.

Abstract: A store-and-forward architecture which stores and distributes information programs to subscribers on demand includes: information warehouses which archive information programs from multiple service vendors and dispense information programs in segments to central offices in high speed bursts; central offices which manages subscriber's request for service and buffers segments of information programs for delivery to subscribers in real-time under the subscriber's interactive control; and customer premises equipment where a subscriber's requests and control signals for interactive play-out of information program are generated and information programs are received for the subscriber's use.

Abstract: A store-and-forward architecture which stores and distributes information programs to subscribers includes: information warehouses which archive information programs and dispense information programs in segments to central offices in bursts; central offices which manage subscriber's requests for service and buffer segments of information programs for delivery to subscribers in real-time under the subscriber's interactive control; and customer premises equipment. The central offices employ CO buffers, and each CO buffer includes: processors, for administering internal buffer operations and processing subscribers requests based upon the service presentation script and a program presentation map; interfaces for providing external access; busses for internal transport; buffer storage for storing segments of information programs; and memory storage for storing the script and map.

Abstract: A switch for receiving packets on optical fiber input trunks and for switching the packets to appropriate optical fiber output trunks is disclosed. The packet switch is a hybrid switch comprising both optical and electronic devices and specifically comprises and electronic input buffer, an optical transport network and an optical control network. The optical transport network prevents internal collisions within the switch and the optical control network prevents external collisions of packets. The packet switch exploits the inherent properties of optical and electronic devices for the specific functions they are best suited for.

Abstract: A multiwavelength optical cross-connect network for a parallel processing computer system is disclosed. Illustratively, in a parallel processing computer system with N processors and M memories, two passive star couplers and a total of 2N+2M optical fiber links, produce a fully connected, internally non-blocking, large throughput, cross-connect network. Illustratively, the cross-connect network utilizes tunable optical sources and heterodyne receivers to deliver information requests from particular processors to particular memories and responses from particular memories to particular processors.

Abstract: A wavelength division multiplexing structure for establishing dedicated high bit rate point-to-point connections between network nodes is disclosed. The information transmitted out of any given network node is modulated on a plurality of wavelengths according to destination. These wavelengthds are multiplexed and transmitted to the network hub. At the hub, all the different wavelengths from all the nodes are demultiplexed, passively rearranged, multiplexed again and transmitted to the appropriate destinations. The information handling capacity of this structure exceeds 1 Terabit/second.