Nortel Networks Corporation

Avaya Inc.

Rockstar Consortium US LP

Ciena Corporation

Rpx Clearinghouse LLC

Other

Apple Inc.

Northern Telecom Limited

Rockstar Bidco, LP

Noretl Networks Limited

Nortel Netwoeks Limited

James Aweya

Delfin Y Montuno

Michel Ouellette

Kent Felske

Ernst A Munter

Abel Clement Dasylva

Zhonghui Yao

Luis Orozco Barbosa

Aneta Wyrzykowska

Victor Firoiu

Michael Mayer

Kah Ming Soh

Genzao G Zhang

Bernard J Doray

Tong Shan

Wenfeng Chen

Mieczyslaw Juliusz Surazski

Bernard Thiboutot

Jeganathan Markandu

Michel Quellette

Pierre A Hamel

Imed Frigui

Luis Orozco-Barbosa

Techniques for time transfer via signal encoding are disclosed. In one particular exemplary embodiment, the techniques may be realized as a method for time transfer via signal encoding comprising generating a time service ordered-set for inclusion in a physical coding sublayer frame of a physical layer device, generating time service data for inclusion in the physical coding sublayer frame of the physical layer device, and transmitting the physical coding sublayer frame.

Techniques for time transfer via signal encoding

Transfer of differential timing over a packet network is provided. A transmitting service interface receives a service clock and is coupled to a receiving service interface through a network backplane. A primary reference clock is provided to time the network backplane. The primary reference clock and the service clock are used to synthesize a copy of the service clock connected to the transmitting service interface. A first control word containing an error differential between the service clock and the synthesized copy of the service clock is generated and transmitted through the network backplane via a packet. The first control word, together with the primary reference clock, is used to recreate the service clock for timing the receiving service interface.

Differential timing transfer over synchronous ethernet using digital frequency generators and control word signaling

A system in which data signatures are used to identify copyrighted content passing through a network. The data signatures are derived from files containing copyrighted content to be identified. The signatures are used to search within peer-to-peer data streams flowing through one or more network nodes in a communications network. Any specific technique may be used for pattern recognition between the signatures and the monitored traffic. When a particular file of interest is identified, the system may operate to perform one or more of several possible actions, including stopping the transmission, allowing the transmission but recording the event, making an offer to the recipient allowing them to legally purchase the file, or sending alternative information or intentionally corrupting the information to render it useless to the recipient.

Method and system for content detection and interception in communication networks

In response to a network topology change, a clock root node calculates a new clock path for each affected node by building a clock source topology tree, and identifying from that tree a path to the network node from a clock source of higher or equal stratum relative to that network node. The root node then sends a network message to each node indicating the new path that the node should use. Each node receives the message and compares the new path with the existing path. If the paths are different then the node acquires the new path just received in the message. If the paths are the same then the node does nothing and discards the message.

Protocol for clock distribution and loop resolution

A method and system for position location of clients in wireless local area networks. (WLANs). The position location technique utilizes time-of-flight (TOF) measurements of signals transmitted from a client to a number of wireless access points (APs) or vice versa to determine distances. Round-trip time (RTT) measurement protocols are used to estimate TOF and distances between the client at an unknown position and the WLAN APs. The method and system improves positioning accuracy by identifying and mitigating non-line-of sight (NLOS) errors such as multipaths. Trilateration algorithms are utilized in combination with median filtering of measurements to accurately estimate the position of the client.

Method and system for wireless LAN-based indoor position location

A timing system for time synchronization between a time server and a time client over a packet network. The timing system includes a time server for generating current timestamp information and a time client having a phase-locked loop driven client clock counter. The time client periodically exchanges time transfer protocol messages with the time server over the packet network, and calculates an estimated client time based on the timestamp information. The phase-locked loop in the time client receives periodic signals representing the estimated server time as its input and calculates a signal which represents the error difference between the estimated server time and the time indicated by the time client clock counter. The error difference eventually converges to zero or a given error range indicating the time presented by the client clock counter, which is driven by the phase-locked loop having locked onto the time of the time server.

Method and apparatus for time and frequency transfer in communication networks

A method, system and master service interface transfer differential timing over a packet network. The transmitting service interface receives a service clock and is coupled to a receiving service interface through a network backplane. A primary reference clock is provided to time the network backplane. The primary reference clock and the service clock are used to synthesize a copy of the service clock connected to the transmitting service interface. A first control word containing an error differential between the service clock and the synthesized copy of the service clock is generated and transmitted through the network backplane via a packet. The first control word, together with the primary reference clock, is used to recreate the service clock for timing the receiving service interface.

Algorithms and data structure are described for constructing and maintaining a clock distribution tree ('CDT') for timing loop avoidance. The CDT algorithms and data structure allows a node to make an automated and unattended path switch to the most desirable clock source in the network. In response to a network topology change, a clock root node distributes new clock paths to all nodes in the network. In particular, the root node calculates a new clock path for each affected node by building a clock source topology tree, and identifying from that tree a path to the network node from a clock source of higher or equal stratum relative to that network node. The root node then sends a network message to each node indicating the new path that the node should use. Each node receives the message and compares the new path with the existing path. If the paths are different then the node acquires the new path just received in the message. If the paths are the same then the node does nothing and discards the message.

A timestamp-based clock synchronization technique is employed for CES in packet networks. The technique is based on a double exponential filtering technique and a linear process model. The linear process model is used to describe the behavior of clock synchronization errors between a transmitter and a receiver. The technique is particularly suitable for clock synchronization in networks where the transmitter and receiver are not driven from a common timing reference but the receiver requires timing reference traceable to the transmitter clock.

Clock synchronization using a weighted least squares error filtering technique

The invention includes a technique for clock recovery in a network having master and slave clocks in respective Time Division Multiplexing ('TDM') network segments which are interconnected by a non-TDM segment. Master clock timestamps are sent to the slave. The slave measures a master clock timestamp inter-arrival interval, and sends slave clock timestamps to the master. The master measures a slave clock timestamp inter-arrival interval, and sends that slave clock timestamp inter-arrival interval to the slave. The slave then calculates an error signal based at least in-part on the difference between the master clock timestamp inter-arrival interval and the slave clock timestamp inter-arrival interval, and employs the difference to recover the first service clock in the second TDM segment.

Three-way message exchange clock synchronization

A technique for adaptively load balancing connections in multi-link trunks is disclosed. The present invention provides an adaptive load balancing algorithm that utilizes relative link quality metrics to adjust traffic distribution between links. Link quality metrics may include short-term averages of an observed packet drop rate for each member link in a bundle. The present invention may dynamically adjust the number of flows on each link in proportion to available bandwidth. In addition, link quality metrics may be equalized, such that no link is more lossy than the others.

Technique for adaptively load balancing connections in multi-link trunks

A method and system for allocating bandwidth of a wireless channel to different types of traffic includes partitioning the bandwidth of the wireless channel into a plurality of contention periods. Traffic flows are associated with access categories, and one or more of the access categories are assigned to each contention period. During at least one of the contention periods, traffic flows associated with a proper subset of the access categories contend for access to the wireless channel.

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Kanata, Canada

James Aweya