| Patent application number | Description | Published |
| 20090177729 | MANAGING WATCHER INFORMATION IN A DISTRIBUTED SERVER ENVIRONMENT - A system for managing watcher information in a distributed server environment, including a watcher information database configured to store records, any of the records populated by a watcher identifier, a presentity identifier, a list of unique identifiers of a plurality of subscriptions by the watcher, a watcher state field indicating a current state of the watcher, and an event field indicating an event that last caused the state of the watcher to change, each record representing a different pair of a watcher and a presentity pair, and where each of the records maintains a single state for one or more subscriptions by a watcher to receive presence information regarding a presentity, and a plurality of presence servers, where each of the presence servers is configured to modify any of the records to reflect the current state of a watcher for any subscription indicated in the record. | 07-09-2009 |
| 20090182809 | ELIMINATING REDUNDANT NOTIFICATIONS TO SIP/SIMPLE SUBSCRIBERS - A system for eliminating redundant notifications to SIP/SIMPLE subscribers, the system including a notification fingerprinter configured to generate a fingerprint from the contents of a SIP/SIMPLE subscriber notification using a predefined fingerprinting method, a fingerprint comparactor configured to compare a fingerprint of a previously-sent notification with a fingerprint of a waiting-to-be-sent notification, and a server configured to send the waiting-to-be-sent notification to the subscriber only if the fingerprints do not match. | 07-16-2009 |
| 20090327494 | COMMON RESOURCE MANAGEMENT IN A SERVER CLUSTER - A system for assigned resource management, including multiple computer servers, each identifiable by an identifier, and a resource table stored on a computer-readable data storage medium and accessible to any of the servers, where any of the servers is configured to establish itself as manager for a resource, if no record in the resource table indicates that a manager exists for the resource, by including its identifier in a record in the resource table for the resource in a manner that indicates that the server is manager for the resource, where any of the servers is configured to include its identifier in a list of servers in the record for the resource that wish to participate in the performance by the manager of at least one action regarding the resource, and where the manager is configured to perform the action regarding the resource. | 12-31-2009 |
| 20110138054 | Optimized Cooperation Between Resource List Servers and Presence Servers - A method, system and computer program product for optimized cooperation between resource list servers and presence servers. The method including receiving a subscription request from a watcher, where the subscription request identifies a resource list and is a request to receive presence information regarding each of a plurality of presentities listed on the resource list, and generating a subscription request to a presence server for presence information regarding any presentity listed on the resource list only if no other currently-active subscription request is known by the resource list server to exist for presence information regarding the presentity. | 06-09-2011 |
| Patent application number | Description | Published |
| 20090073560 | Systems and Methods for Polarization Mode Dispersion Mitigation - In one exemplary embodiment, a method comprises transmitting an optical signal via the optical line, measuring a relative change in spectral intensity of the optical signal near a clock frequency (or half of that frequency) while varying a polarization of the optical signal between a first state of polarization and a second state of polarization, and using the relative change in spectral intensity of the optical signal to determine and correct the DGD of the optical line. Another method comprises splitting an optical signal traveling through the optical line into a first and second portions having a first and second principal states of polarization of the optical line, converting the first and second portions into a first and second electrical signals, delaying the second electrical signal to create a delayed electrical signal that compensates for a DGD of the optical line, and combining the delayed electrical signal with the first electrical signal to produce a fixed output electrical signal. | 03-19-2009 |
| 20090073561 | Systems and Methods for Polarization Mode Disperson Mitigation - In one exemplary embodiment, a method comprises transmitting an optical signal via the optical line, measuring a relative change in spectral intensity of the optical signal near a clock frequency (or half of that frequency) while varying a polarization of the optical signal between a first state of polarization and a second state of polarization, and using the relative change in spectral intensity of the optical signal to determine and correct the DGD of the optical line. Another method comprises splitting an optical signal traveling through the optical line into a first and second portions having a first and second principal states of polarization of the optical line, converting the first and second portions into a first and second electrical signals, delaying the second electrical signal to create a delayed electrical signal that compensates for a DGD of the optical line, and combining the delayed electrical signal with the first electrical signal to produce a fixed output electrical signal. | 03-19-2009 |
| 20090080883 | Systems and Methods for Polarization Mode Dispersion Mitigation - In one exemplary embodiment, a method comprises transmitting an optical signal via the optical line, measuring a relative change in spectral intensity of the optical signal near a clock frequency (or half of that frequency) while varying a polarization of the optical signal between a first state of polarization and a second state of polarization, and using the relative change in spectral intensity of the optical signal to determine and correct the DGD of the optical line. Another method comprises splitting an optical signal traveling through the optical line into a first and second portions having a first and second principal states of polarization of the optical line, converting the first and second portions into a first and second electrical signals, delaying the second electrical signal to create a delayed electrical signal that compensates for a DGD of the optical line, and combining the delayed electrical signal with the first electrical signal to produce a fixed output electrical signal. | 03-26-2009 |
| 20090279902 | METHOD AND APPARATUS FOR DEMODULATING AND REGENERATING PHASE MODULATED OPTICAL SIGNALS - A DPSK/DQPSK receiver includes an optical splitter that separates the received DPSK/DQPSK optical signal according to an optical power splitting ratio into a plurality of received optical signals. A plurality of optical filters passes a plurality of filtered received optical signals. A plurality of optical detectors generates a plurality of electrical detection signals, each with a power that is related to a power of a respective filtered optical signal. A plurality of amplifiers generates a plurality of amplified electrical signals. At least one electrical signal combiner combines the plurality of amplified electrical detection signals generated by the plurality of optical amplifiers into a combined reception signal. | 11-12-2009 |
| 20110142445 | Systems and Methods for Polarization Mode Dispersion Mitigation - In one exemplary embodiment, a method comprises transmitting an optical signal via the optical line, measuring a relative change in spectral intensity of the optical signal near a clock frequency (or half of that frequency) while varying a polarization of the optical signal between a first state of polarization and a second state of polarization, and using the relative change in spectral intensity of the optical signal to determine and correct the DGD of the optical line. Another method comprises splitting an optical signal traveling through the optical line into a first and second portions having a first and second principal states of polarization of the optical line, converting the first and second portions into a first and second electrical signals, delaying the second electrical signal to create a delayed electrical signal that compensates for a DGD of the optical line, and combining the delayed electrical signal with the first electrical signal to produce a fixed output electrical signal. | 06-16-2011 |