摘要:
In one embodiment, line cards of packet switching or other network devices are configured for terminating pseudowires. Typically, this includes multiple line cards being configured for terminating a same pseudowire, which allows the corresponding pseudowire traffic to be received by any one of these multiple line cards. Each of these pseudowire-terminating line cards is typically configured to apply one or more features to a pseudowire packet. Examples of these features include, but are not limited to: Access Control List, Quality of Service, Netflow, and Lawful Intercept. For a received packet to be sent out one of these pseudowires, a two-stage lookup operation can be used to first identify the pseudowire over which to forward the packet; and a second lookup operation based on the pseudowire to identify forwarding information corresponding to a path through a network over which a corresponding pseudowire is configured.
摘要:
In one embodiment, line cards of packet switching or other network devices are configured for terminating pseudowires. Typically, this includes multiple line cards being configured for terminating a same pseudowire, which allows the corresponding pseudowire traffic to be received by any one of these multiple line cards. Each of these pseudowire-terminating line cards is typically configured to apply one or more features to a pseudowire packet. Examples of these features include, but are not limited to: Access Control List, Quality of Service, Netflow, and Lawful Intercept. For a received packet to be sent out one of these pseudowires, a two-stage lookup operation can be used to first identify the pseudowire over which to forward the packet; and a second lookup operation based on the pseudowire to identify forwarding information corresponding to a path through a network over which a corresponding pseudowire is configured.
摘要:
A system and method for advertising out-of-resources (OOR) conditions for entities, such as nodes, line cards and data links, in a manner that does not involve using a maximum cost to indicate the entity is “out-of-resources.” According to the technique, an OOR condition for an entity is advertised in one or more type-length-value (TLV) objects contained in an advertisement message. The advertisement message is flooded to nodes on a data network to inform them of the entity's OOR condition. Head-end nodes that process the advertisement message may use information contained in the TLV object to determine a path for a new label switched path (LSP) that does not include the entity associated with the OOR condition.
摘要:
In one embodiment, a Bidirectional Forwarding Detection (BFD) asynchronous mode session is established between two packet switching devices interconnected by one or more physical links. Prior to L2 or L3 services being established, each of these packet switching devices does not know the Media Access Control (MAC) nor Internet Protocol (IP) addresses of each interface of the other packet switching device that is connected to one of these link(s). A request to establish a BFD session is sent from one packet switching device to the other, with a MAC frame including the request being addressed to a group, broadcast, or other address that the receiving packet switching device will recognize and thus process the received request. Based on information contained in this received MAC frame, the receiving packet switching device has the information it needs, and sends a BFD control frame to the other packet switching device.
摘要:
Disclosed are, inter alia, methods, apparatus, computer-storage media, mechanisms, and means associated with the coordinated updating of forwarding information bases (FIBs) in a multistage packet switching device, which performs at least lookup operations on multiple different FIBs in determining how to forward a packet. One embodiment uses lookup operations on two different FIBs, with these being an ingress FIB on an ingress line card and an egress FIB on an egress line card. In response to a change in the forwarding information for a stream of packets, the egress FIBs are first updated to include both the old and new forwarding information. After all egress FIBs have been updated, the ingress FIBs are updated to use the new forwarding information. This update procedure is designed to eliminate loss or duplication of packets induced during the updating of these FIBs to use the new forwarding information.
摘要:
An example method includes detecting a failure at a first network element, the failure is associated with a link between the first network element and a second network element. The method also includes generating a list of network elements to be notified based on the failure, the second network element is included on the list. The method further includes generating an alarm indication signal (AIS) message, the AIS message identifies a plurality of tunnels affected by the failure. The AIS message is communicated to the second network element. In more detailed embodiments, each link between the first network element and the second network element includes a globally unique link identifier, which includes an associated autonomous system number. The globally unique link identifier can represent a string to be associated with the plurality of tunnels, the globally unique link identifier includes a source address and a destination address.
摘要:
In one embodiment, an access component of a local network edge device receives traffic, and generates a frame for the traffic that includes a remote context label that identifies an access component of the remote network edge device to which the traffic is to be forwarded upon arrival at the remote network edge device, and a virtual circuit label corresponding to a particular virtual service of the traffic. The local network edge device forwards the frame towards the remote network edge device. In another embodiment, the frame may be received at a core component of the remote network edge device, an in response to the remote context label identifying an access component of the remote network edge device, forwarded to the access component, which determines the particular virtual service, and forwards the traffic from the frame out the access component towards an endpoint for the traffic.
摘要:
In one embodiment, an edge device of a core network may receive a plurality of packets from a peripheral network having a plurality of active connections to the core network, where each packet has a destination address and a source address. The edge device may compute a hash on the destination address or the source address of each packet, and determine whether the computed hash corresponds to the edge device. In response to the computed hash not corresponding to the edge device, the edge device may drop the packet, and in response to the computed hash corresponding to the edge device, the edge device may process the packet to forward the packet, where the dropping and processing load balances the plurality of packets over the active connections and prevents formation of loops in the core network.
摘要:
In one embodiment, a method includes determining when a predetermined period of time has elapsed, and determining whether at least a first message has been obtained on a first port of a node during the predetermined period of time when it is determined that the predetermined period of time has elapsed. The method also includes identifying the first port as being connected to a single-homed site when it is determined that the at least first message has not been obtained on the first port during the predetermined period of time. The first port is identified as being connected to a multi-homed network, a multi-homed device, or a hierarchical Ethernet segment when it is determined that the at least first message has been obtained on the first port during the predetermined period of time.
摘要:
An example method is provided that includes determining whether an address resolution protocol reply from a local machine has been received at an edge node; updating a local cache based on the reply from the local machine; and sending the reply to a plurality of edge nodes through a data plane of a data center interconnect. In more specific implementations, the method can include determining whether an address resolution protocol request has been received from the local machine. The method could also include updating a local machine cache based on the request. In certain implementations, the method can include determining whether the request is targeting the local machine; and dropping the request if the request is targeting the local machine. The method could also include sending the request through the data center interconnect if the request is not targeting the local machine.