Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: The label distribution protocol (LDP) is extended to set up a point to multi-point (P2MP) label switched path (LSP) across a computer network from a source network device to one or more destination network devices. LDP is extended to create a P2MP label map message containing a label and a P2MP forwarding equivalence class (FEC) element having a root node address and an identifier. The P2MP FEC element may, for example, associate an address of the root node of the P2MP LSP with an opaque identifier. The P2MP FEC element uniquely identifies the P2MP LSP. The P2MP FEC element may be advertised with a label in a P2MP label map message. A source network device or the destination network devices may initiate setup and teardown of the P2MP LSP. The P2MP label map messages may be propagated from the destination network devices to the source network device.

Abstract: Scheduling virtual upstream channels within one physical upstream channel is disclosed. The MAP messages of the virtual upstream channels that share the same physical upstream channel are synchronized together such that any one transmission opportunity for a given virtual upstream channel does not overlap with transmission opportunities of any other virtual channel. This includes converting all requests for transmission opportunities into a common unit and then scheduling these requests as appropriate.

Abstract: Principles of the invention relate to techniques for transmission of Layer 2 (L2) traffic over a point to multi-point (P2MP) label switched path (LSP) within a multi-protocol Label Switching (MPLS) network. A source or ingress network device may implement the techniques to connect multiple L2 interfaces to a P2MP LSP within an MPLS network via a P2MP Pseudo-Wire (PW) mechanism that emulates delivery of L2 data units over a packet switched network, such as the MPLS network. The ingress network device first establishes the P2MP LSP and then connects two or more L2 interfaces to the P2MP LSP via the P2MP PW mechanism. Egress network devices may also implement the techniques to terminate the P2MP LSP and de-multiplex traffic arriving via multiple P2MP PWs carried over the same P2MP LSP.

Abstract: Constraint information associated with peering links is taken into account when establishing label switched paths (LSPs) to exit points of a network. Devices within the network, such as routers, designate interfaces associated with peering links as “passive interfaces” to indicate that the interfaces should be included for bandwidth accounting purposes and internal path computation. Other devices within the network utilize the constraint information, e.g., bandwidth availability, when computing and establishing LSPs to the exit points of the network to avoid congested peering links.

Abstract: Principles of the invention are described for providing virtual private local area network service (VPLS) multicast instances across a public network by utilizing multicast trees. In particular, the VPLS multicast instances transport layer two (L2) multicast traffic, such as Ethernet packets, between customer networks via the public network. The principles described herein enable VPLS multicast instances to handle high bandwidth multicast traffic. The principles also reduce the state and the overhead of maintaining the state in the network by removing the need to perform snooping between routers within the network.

Abstract: Principles of the invention are described for providing multicast virtual private networks (MVPNS) across a public network that are capable of carrying high-bandwidth multicast traffic with increased scalability. In particular, the MVPNs may transport layer three (L3) multicast traffic, such as Internet Protocol (IP) packets, between remote sites via the public network. The principles described herein may reduce the overhead of protocol independent multicast (PIM) neighbor adjacencies and customer control information maintained for MVPNs. The principles may also reduce the state and the overhead of maintaining the state in the network by removing the need to maintain at least one dedicated multicast tree per each MVPN.

Abstract: Dynamic subscriber interfaces in a network device are provided. An input port receives data units from multiple subscribers. A primary interface extracts source identifiers from headers associated with the received data units and creates dynamic subscriber interfaces to allocate network device resources to each of the multiple subscribers based on the extracted source identifiers.

Abstract: A system provides congestion control in a network device. The system includes multiple queues, a dequeue engine, a drop engine, and an arbiter. The queues temporarily store data. The dequeue engine selects a first one of the queues and dequeues data from the first queue. The drop engine selects a second one of the queues to examine and selectively drop data from the second queue. The arbiter controls selection of the queues by the dequeue engine and the drop engine.

Abstract: A media gateway is coupled to an Internet Protocol (IP) network through a router. The router and the media gateway communicate through a slim protocol that allows the media gateway to reserve connections over the IP network that have certain minimum bandwidth and latency attributes. The router handles the obtaining of the requested IP circuit for the client. The media gateways only need to execute a relatively simple client application and do not have to be independently capable of obtaining IP-QoS information from the IP network.

Abstract: A network device includes an initial data source to store configuration data for the network device, and a management module to generate a configuration patch that lists any differences between a working copy of the initial data source and the initial data source. The management module modifies the working copy based on configuration commands received from a client, and updates the initial data source in accordance with the differences defined by the configuration patch. During the update process, the management module verifies that any conditions specified by the patch are satisfied. The management module may generate the configuration patch in response to a first command from a client, and apply the patch in response to a second command from the client. The configuration patch may be communicated to other network devices for configuring the devices.

Abstract: Methods of screening incoming packets are provided. A first firewall detects a tunnel formation. A second firewall maintains a list of open firewall sessions. Each tunnel has one or more associated firewall sessions. The first firewall detects variable situations, such as when the tunnel is torn down, and notifies the second firewall so that, for example, the second firewall can act to clear an associated firewall session from the firewall session list. Incoming packets that are associated with firewall sessions that have been cleared from the firewall session list may not be passed through the second firewall.

Abstract: A packet scheduler is configured to perform quality of service (QoS) scheduling on a per-data unit basis. A downstream processing engine is operatively connected to the packet scheduler for receiving forwarded packets. A feedback path is operatively connected between the downstream processing engine and the packet scheduler for transmitting a net data unit change value reflecting a change in packet size between an output of the packet scheduler and an output of the downstream processing engine.

Abstract: Techniques are described for aggregating multiple media packets to improve end-to-end bandwidth efficiency. The techniques include using an RTP aggregation protocol that is not sensitive to packet loss to aggregate multiple media packets under a single header. According to the RTP aggregation protocol, the single header for an aggregated media packet comprises a version field, a zero field, a sequence number field and a trunk ID field. The single header encapsulates the aggregated payload, which is an aggregation of Real-Time Protocol (RTP) segments. An RTP segment either has a compressed format or an uncompressed format. The uncompressed RTP segment includes the complete uncompressed RTP packet copied from the original User Datagram Protocol (UDP) packet. The compressed RTP segment includes the payload of the original RTP rather than the complete original RTP packet.

Abstract: A standalone router is integrated into a multi-chassis router. Integrating the standalone router into a multi-chassis router requires replacing switch cards in the standalone router with multi-chassis switch cards. The multi-chassis switch cards forward packets to a central switch card chassis for routing within the multi-chassis router. By incrementally replacing standalone switch cards with multi-chassis switch cards in the standalone router, packet forwarding performance is maintained during the integration.

Abstract: An apparatus for remotely releasing a connector, e.g., an RJ-45 connector, is described. Embodiments of the invention allow a user to release a cable comprising a connector from a connector jack when the connector jack is difficult to reach. The invention may be particularly useful to release cables from devices comprising an array of connector jacks.

Abstract: A network device receives control plane packets and data plane packets from a network. The network device includes a forwarding component that forwards the data plane packets in accordance with routing information maintained by a routing component. The forwarding component directs the control plane packets to a firewall component that processes the control plane packets to apply firewall services and detect network attacks. After processing, the firewall component loops the control plane packets back to the forwarding components for forwarding to the routing component. The firewall component may be a security service card.

Abstract: A network device switches variable length data units from a source to a destination in a network. An input port receives the variable length data unit and a divider divides the variable length data unit into uniform length data units for temporary storage in the network device. A distributed memory includes a plurality of physically separated memory banks addressable using a single virtual address space and an input switch streams the uniform length data units across the memory banks based on the virtual address space. The network device further includes an output switch for extracting the uniform length data units from the distributed memory by using addresses of the uniform length data units within the virtual address space. The output switch reassembles the uniform length data units to reconstruct the variable length data unit. An output port receives the variable length data unit and transfers the variable length data unit to the destination.

Abstract: A network device is described in which a dedicated resource scheduler monitors memory consumption to provide for improved processing of communication sessions. The scheduler maintains a dependency list of communication sessions, and reserves memory for communication sessions as requests for memory are received. The amount of memory reserved is determined based on the amount of memory currently reserved for the communication sessions in the dependency list. The network device may control ongoing communication sessions by way of window manipulation. Communication sessions are processed in a first mode when available memory has not reached a predetermined amount, while communication sessions are processed in a second mode when available memory reaches a predetermined amount.

Abstract: The present invention relates to workflow systems and methods. In one embodiment, the invention relates to integration of a calendar system with a workflow system where a calendar event can initiate a workflow by sending a message to a form route manager. The completion of a workflow or step in the workflow can result in sending a message to a calendar system to generate an event. In another embodiment, the invention relates to the integration of workflow with a project management system that includes project segments, which are processes that can be defined and controlled by workflow routes. The project management system sends a message to the workflow system to initiate workflow and the workflow system sends a message to the project management system, for example, at the completion of the workflow route. The relationship between the workflow routes can maintain the relationship between the project segments.