Abstract: The bandwidth of a virtual circuit is changed when the aggregate bandwidth available on path(s) to an adjacent ATM device (through which the VC is provided) changes. The change of bandwidth may be implemented by changing the QoS parameters associated with the virtual circuits. Thus, for example, when one of the paths becomes non-operational, the bandwidth of a virtual circuit may be reduced in a fair manner.

Abstract: A method and system for establishing a call between two endpoints residing on different media gateways in a decomposed voice over packet architecture. Cluster attributes identifying alternate bearer possibilities are exchanged between media gateways as part of capabilities negotiation which occurs during call setup conducted by an external call control element over a core network. The media gateways analyze the cluster attributes to determine whether bearer possibilities exist apart from the core network. If an alternate bearer possibility exists, the alternate is employed and the call is established via the alternate bearer directly between the media gateways, thus bypassing the core network.

Abstract: A method for determining a cumulative network layer reachability cost of traversing one or more autonomous network routing systems comprises receiving first network route information from an originating customer edge router, wherein the first network route information identifies a route in a customer network; determining a transit cost from the provider edge router to an endpoint associated with the originating customer edge router based upon a metric value received in a cost community attribute; repeating the determining step for each of one or more autonomous systems that lie in a path from the originating customer edge router to a destination customer edge router, to result in determining an accumulated transit costs across one or more autonomous systems; and determining, based at least in part upon the accumulated transit cost, a best path from the provider edge router to the endpoint associated with the originating customer edge router.

Abstract: Techniques are provided to determine a more realistic measure of a physical carrier-to-interference plus noise radio (pCINR) associated with a wireless channel between first and second wireless communication devices. Channel conditions are used to derive a channel margin quantity that is in turn used “discount” the pCINR. The discounted pCINR is then used to determine a modulation and encoding scheme that can be used on the wireless channel for communications between the first and second wireless communication devices.

Abstract: In one embodiment, a method generally includes identifying at a local Virtual Private LAN Service Provider Edge (VPLS PE) device whether remote VPLS PE devices are configured for operation as a Provider Backbone Bridge (PBB), negotiating pseudowire connections with the remote VPLS PE devices based on identification of the remote VPLS PE device configuration, receiving a frame destined for one of the remote VPLS PE devices, and transmitting the frame in a format compatible with the remote VPLS PE device. The local VPLS PE is configured for operation as a PBB and at least one of the remote VPLS PE devices is not configured for operation as a PBB. An apparatus for use in mixed mode VPLS network is also disclosed.

Abstract: A method is disclosed for application layer message-based network element management of server failures. According to one aspect, a network element such as a router intercepts session state information that is contained in a request from a client and locally stores the session state information. As a result, application servers to which the requests are directed do not need to store the session state information. If an application server fails, then the network element can use the session state information stored at the network element to continue the session with another application server, transparently to the client application that is involved in the session.

Abstract: The invention provides a method and system of detecting aliases in a network. The network comprises at least one device and at least one Network management system (NMS) for managing the devices. The NMS identifies each device available in the network with a message digest. The NMS retrieves the message digest of a device that is submitted for management. The NMS tries to locate the retrieved message digest with a database of message digests. In case the retrieved message digest is located on the database, the NMS declares the device as an alias. However, if the message digest is not located on the database, the NMS stores the message digest in the database and starts managing the device.

Abstract: In one embodiment, a method includes identifying a critical time when a current presence state associated with a first client is scheduled to change to a timed presence state. The method also includes generating a first presence document before the critical time, and providing the first presence document to at least a second client. The first presence document has an indication of the current presence state and the timed presence state, and is provided to the second client before the critical time.

Abstract: Method and apparatus including registering a first spoke router with a hub router, forwarding an Internet Protocol version Four (IPv4) data packet from the first spoke router to a second spoke router over an Internet Protocol version Six (IPv6) multipoint tunnel via the hub router, transmitting a binding information associated with the first spoke router from the hub router to the second spoke router, and establishing a direct communication path by the second spoke router with the first spoke router based on the received binding information are provided.

Abstract: Improved lumped Raman amplification systems are disclosed. A lumped Raman amplification structure provides optimized efficiency, low noise figure over a range of gain settings, and a high saturation threshold. Responsibility for amplifying different portions of the spectrum is divided among multiple stages. In one particular implementation, two outer stages amplify a first band and two inner stages amplify a second band. The two inner stages also apply a small amount of amplification to the first band. A modification improves noise figure in the second band by adding some amplification in the second band to the first stage.

Abstract: A conferencing system includes a plurality of ports for network connection to endpoint devices of participants to a conference session. A mixer receives input audio streams from the endpoint devices and then outputs a mixed audio stream back to the endpoint devices. A processor runs a program that automatically downgrades one or more of the participants to the conference session from a full-duplex communication mode to a half-duplex communication mode in response to an event affecting allocation of conferencing resources, the conferencing resources including the ports.

Abstract: A method and system for filtering traffic in a multicast network are disclosed. Multicast packets are received at a network device which has a multicast routing table and a list containing nodes or interfaces authorized for transmitting multicast traffic into the network at the network device. The method includes determining if the network device is directly connected to a source of the multicast packet and only if the network device is directly connected to the source of the multicast packet, checking the list to determine if the source is an authorized source and dropping or blocking multicast packets from the source if the source is not an authorized source. The method further includes processing multicast packets from the source according to the multicast routing table.

Abstract: Disclosed are methods and apparatus for translating data within a cable network between a first voice-over-IP (VOIP) protocol used by a user agent and a second VOIP protocol used by a call management server, or other type of call receiver. In one embodiment, data from an SIP (Session Initiation Protocol) user agent is translated for an NCS (Network Call Signaling) call management server. In one implementation, translation mechanisms are provided within the customer premises equipment in which the respective user agent is also configured.

Abstract: In one embodiment, a signaling message is received from an endpoint. It is determined from the signaling message whether, prior to sending the signaling message, the endpoint performed network address translation on the body of the signaling message. If it is determined from the signaling message that, prior to sending the signaling message, the endpoint did not perform network address translation on the body of the signaling message, application layer gateway functionality is applied to the body of the signaling message such that a modified signaling message is generated.

Abstract: A system for providing location-specific sound in a telepresence system includes a plurality of remote microphones. Each remote microphone is associated with a respective area and operable to generate a sound signal from the voice of at least one user within the respective area. The system also includes a plurality of remote cameras. Each remote camera is associated with a respective remote microphone of the plurality of remote microphones and aligned to generate an image of its associated respective area. The system further includes a plurality of local displays. Each local display is operable to reproduce the image of a respective area generated by a respective remote camera. The system also includes a plurality of local loudspeakers. Each local loudspeaker is positioned proximate to a respective local display and operable to reproduce the sound signal from the voice of the at least one user within the respective area reproduced by the respective local display.

Abstract: Disclosed are methods and apparatus for providing redundant data forwarding or routing capabilities. In one embodiment, a network device includes a designated router and a non-designated router. The designated router generally provides layer 3 switching or routing for data received into the network device. Although the non-designated router is active, it generally does not provide forwarding capabilities until the designated router fails. The non-designated router's logical interfaces are disabled, while the designated router's logical interfaces are enabled. The non-designated router becomes the new designated router when the first designated router fails. In general terms, the routers of the network device provide redundancy with the network being aware of only a single router within network device. That is, the network is only aware of a single router. This is accomplished by having the routers share the same IP and MAC address on each logical interface.

Abstract: A server is configured for preventing flood attacks by a client having sent a request, by dynamically generating a challenge to be performed by the client before the server will perform any work for the client. The challenge includes a dynamically generated computational request and a dynamically generated secure cookie. The server generates a first hash result based on hashing a first random number, having a prescribed length, with a second random number having a dynamically selected length. A secure cookie is generated based on hashing the first hash result with a prescribed secure key known only by the server, and a unique identifier for the request such as the client network address with a time stamp. The challenge requires the client to determine the second random number based on the first random number and the hash result. The server validates the challenge results using the secure cookie.

Abstract: A dispatching technique dispatches packets to a plurality of service control engines (SCEs) which in aggregate may be configured to handle traffic produced by a high-speed high-capacity data link. Upstream and downstream packets that are associated with a data flow between a subscriber and a destination node in a communication network are received from by a dispatcher which is located in a path used by the data flow. For each packet, the dispatcher identifies an SCE from among a plurality of SCEs that is to receive the packet based upon an address contained in the packet. The packet is then dispatched by the dispatcher to the identified SCE which processes the packet accordingly. After processing the packet, the SCE returns the packet to the dispatcher which further processes the packet including transferring the packet onto the communication network towards its destination.

Abstract: Each network node having at least one destination-oriented link toward a directed acyclic graph (DAG) destination can receive a corresponding set of path performance metrics via the destination-oriented link. The set of path performance metrics, initiated by the DAG destination outputting initial link metrics on each of its source-connecting links, identifies aggregate link metrics for a corresponding path to the DAG destination via the corresponding destination-oriented link. The network node outputs a corresponding updated set of path performance metrics on each of its source-connecting links based on the received set of path performance metrics and the corresponding link metric for the corresponding source-connecting link. Hence, each network node in the DAG can assess the performance of each connected path to the DAG destination, and forward a data packet via a selected destination-oriented link based on the corresponding path performance metrics and forwarding policies for the forwarded data packet.

Abstract: Methods and apparatus for determining that all conductors of an Ethernet connection are connected to the same powered device (PD). In one disclosed embodiment, it is first determined that a signal conductor pair of the Ethernet connection is coupled to a valid PD according to a discovery process, and the unused conductor pair of the Ethernet connection is also coupled to a valid PD. However, it is not yet determined whether they are both coupled to the same PD. This disclosure provides for injecting a polluting signal into one of the conductor pairs, and performing the discovery process on the other conductor pair. If the discovery process fails on the other conductor pair as a result of the polluting signal, then it is determined that both of the conductor pairs are indeed coupled to same PD.