Abstract: A computer network processes data packets in the event of a network link failure. The network includes a plurality of routers that deliver data packets to the network via a plurality of links. At least one router includes a protection cycle manager. The protection cycle manager has a protection cycle packet identifier and a protection cycle packet processor. The protection cycle packet identifier identifies, as protection cycle packets, data packets having a specific protection cycle format. The protection cycle packet processor processes protection cycle packets to determine whether the packet destination corresponds to the routing node, and if the packet destination corresponds to the routing node, the protection cycle packet is treated by the routing node as a data packet received from the packet source via the failed link. Otherwise, if the packet destination does not correspond to the routing node, the protection cycle packet is sent to a protection cycle node for the routing node.

Abstract: A system, method and apparatus for facilitating handoff of communications with a user device between a first communication network having a first domain technology, and a second communication network having a second domain technology different from the first domain technology, the system, method and apparatus includes an anchor point that establishes a first service flow with the first communication network, and a second service flow with the second communication network based upon a triggering event respectively, with the user device, and a handoff device that receives at least one handoff parameter for determining a handoff operation of the user device from the first communication network to the second communication network.

Abstract: A novel beacon-based position location technique for efficient location discovery of untethered clients in packet networks is disclosed. The position location technique utilizes the time-difference-of-arrival (“TDOA”) of a first signal transmitted by a beacon of known location and a second signal transmitted by an untethered client. The TDOA of these two signals is measured locally by at least three non-collinear signal receivers. For each of the receivers, the TDOA is used to calculate a perceived distance to the client. A circle is then calculated for each receiver, centered on the receiver and having a radius equal to the perceived distance. At least two lines defined by points of intersection of the calculated circles are then calculated. The point of intersection of the lines represents the location of the client. To facilitate operation, the signal receivers may be arranged on vertices which define a convex polygon as viewed from above.

Abstract: Disclosed is an Active Queue Management method and apparatus which uses traffic rate information for congestion control. Using a nonlinear fluid-flow model of Traffic Control Protocol, a proportional-integral controller in a closed loop configuration with gain settings characterized for stable operation allows a matching of the aggregate rate of the active TCP connections to the available capacity. Further disclosed is a method for calculation of the regime of gain settings for which stable operation of a given network obtains. This approach allows for capacity matching while maintaining minimal queue size and high link utilization.

Abstract: A telecommunication station set such as an IP phone is configured based on proximity of a user. Proximity of the user relative to the station set can be determined using RF-ID, UWB, GPS, direct user input, contextual information or other technology. For example, the user may carry a badge equipped with an RF-ID tag. The RF-ID tag is operative in response to an RF-ID reader associated with the phone, when in close proximity, to signal user ID and password, which may be encrypted. The user ID and password are sent to a SIP server, which authenticates the user and retrieves user-specific configuration details which are returned to the IP phone. The IP phone configures itself with the user-specific parameters. If the user moves away from the phone, as determined by the RF-ID tag being out of range of the reader, the IP phone de-configures itself.

Abstract: A method and system for monitoring context information associated with a wireless communication entity for determining a potential occurrence of a network disruption for that wireless communication entity. Upon determining a potential occurrence of a network disruption, causing an adjustment of bandwidth available for data transfer involving the wireless communication entity. The adjustment is used to prevent or mitigate service disruptions.

Abstract: The present invention relates to a system and method for providing power management to sensing nodes in a sensor network. A system may include a plurality of sensing nodes, each sensing node connected through a power management device to an external power source, such as a powered node of another network, for managing power from the external power source to the sensing node. Beneficially, a plurality of power management devices allow for a sensor network of fixed or mobile wireless sensing nodes or sensor gateways to make use of power from an external source such as an another network e.g. an existing emergency lighting system or other similar powered building system. Thus for example, a sensor or group of sensing nodes and their associated power management devices may be integral with or co-located in proximity to powered nodes of these other networks.

Abstract: 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.

Abstract: This invention provides a system, method and apparatus for facilitating handoffs from a first communication network to a second communication network, the first communication network and second communication network being heterogeneous with respect to each other. The system, method and apparatus may further include a contextual information server, which stores contextual elements corresponding to a user device and the operating environment of the user device, and a handoff decision function module that evaluates at least one of the contextual elements to determine whether to handoff user device communications from the first communication network to the second communication network.

Abstract: A method for dynamically adjusting jitter buffer size according to buffer fill dynamics is disclosed. In one embodiment, an upper threshold and lower threshold for the jitter buffer are identified, wherein the lower buffer threshold identifies a minimum desirable number of packets in the jitter buffer, and the upper buffer threshold identifies a maximum desirable number of packets in the jitter buffer. Operating characteristics of the jitter buffer are monitored to identify instances when the jitter buffer size falls below or exceeds the desired thresholds. When a threshold is crossed, the adaptive algorithm alters the playback offset time, by introducing or deleting packets into the transmission path, to allow the jitter buffer size to return to a desirable target size within the threshold boundaries.

Abstract: Disclosed is a rate-based multi-level Active Queue Management with drop precedence differentiation method and apparatus which uses traffic rate information for congestion control. Using a nonlinear fluid-flow model of Traffic Control Protocol, an integral controller in a closed-loop configuration with gain settings characterized for stable operation allows a matching of the aggregate rate of the active TCP connections to the available capacity. Further disclosed is a method for calculation of the regime of gains over which stable operation of a given network obtains. An enhancement of the basic algorithm provides the ability to drop low-precedence packets in preference to higher precedence packets. This approach allows for a rate-based AQM approach for application in a differentiated service environment.

Abstract: An optical network unit (ONU) interconnected by passive optical network (PON) equipment to an optical line terminal (OLT) is identified using secondary modulation of the optical carrier to impress an identifier of the ONU onto the carrier. This resolves a recurring ONU failure mode detection problem caused by failure of a laser driver that causes the ONU to be stuck in an on state.

Abstract: Disclosed is an Active Queue Management method and apparatus which uses traffic rate information for congestion control. Using a nonlinear fluid-flow model of Traffic Control Protocol, an integral controller in a closed loop configuration with gain settings characterized for stable operation allows a matching of the aggregate rate of the active TCP connections to the available capacity. Further disclosed is a method for calculation of the regime of gains for which stable operation of a given network obtains. This approach allows for capacity matching while maintaining minimal queue size and high link utilization.

Abstract: Documents written using a markup language such as XML may be decomposed into Path and Parent Associated Node (PPAN) elements, each of which is a linear data structure that includes the content of a node, the parent-child relationship of the node, and the path level of the node. A number of PPAN elements may be grouped together to form A PPAN chain. A PPAN matching process uses the PPAN elements/PPAN chain to search for structured documents that match the PPAN chain. The PPAN matching process is able to perform query and match at the same time to accelerate the PPAN matching process, and also enables complex services to be represented by generic structured documents. Optionally, the PPAN matching process may support wildcard requests so that services may be discovered without prior knowledge of the services.

Abstract: Disclosed is an Active Queue Management method and apparatus which uses traffic rate information for congestion control. Using a nonlinear fluid-flow model of Traffic Control Protocol, a proportional controller in a closed loop configuration with gain settings characterized for stable operation allows a matching of the aggregate rate of the active TCP connections to the available capacity. Further disclosed is a method for calculation of the regime of gains for which stable operation of a given network obtains. This approach allows for capacity matching while maintaining minimal queue size and high link utilization.

Abstract: System and method for dynamically reconfiguring communications session routing in a communications system, each communications session being destined for a particular entity and being associated with at least one predefined route. Location information indicative of a current location for the particular entity is obtained and applied, in combination with at least one other type of information affecting routing of communications sessions to the particular entity, to a predefined set of conditional routing rules associated with the particular entity. This rules-based processing generates a routing result, on the basis of which the at least one predefined route associated with each communications session destined for the particular entity is dynamically updated. The at least one other type of information affecting routing of communications sessions to the particular entity may include presence information, location-enhanced presence information, entity profile information and administrative information.

Abstract: System and method for determining location-enhanced presence information for a particular entity subscribed to a communications system. Location information indicative of a current location for the particular entity is obtained, as well as presence information indicative of a current activity status of the particular entity within the communications system. A combination of the current location and current activity status of the particular entity is applied as a condition to a set of conditional rules associated with the particular entity, for determining current location-enhanced presence information for the particular entity.

Abstract: System and method for dynamically re-directing communications sessions destined for a particular entity in a communications system, each communications session being associated with at least one predefined route. Location information indicative of a current location of the particular entity is obtained and applied to a predefined set of conditional routing rules associated with the particular entity. This rules-based processing generates a routing result, on the basis of which the at least one predefined route associated with each communications session destined for the particular entity is dynamically updated.

Abstract: Where a common network clock is available at both a TDM receiver and a TDM transmitter which communicate via a packet network, differential clock recovery can be accomplished by matching the number of service clock pulses in a network reference clock period at the transmitter and receiver. In one embodiment the transmitter need only send a counter value from a counter that is clocked and reset, respectively, by the service clock and network reference clock, thereby allowing use of different types of oscillators, both analog and digital, to be implemented at the transmitter and receiver. The technique is also general enough to be applied in a wide variety of packet networks including but not limited to IP, MPLS and Ethernet. In an alternative embodiment, a faster derived network clock fdnc drives both the transmitter and receiver counters, which in turn are reset, respectively by the slower transmitter service clock fsc and slower receiver service clock frc.

Abstract: 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.