Cisco Technology, Inc.

Heidi H Ou

Yiqun Cai

Steven Vincent Luong

James L Ng

Steven Edward Moore

Richard W Bradford

Rena Whei-Ming Yang

Gerald Redwine

Kevin M Eckhardt

Scott R Sturgess

Toerless Eckert

Sridhar Vallepalli

Liming Wei

Apoorva Karan

Yongkui Han

Rena W Yang

Xiang Zheng

Methods for distributing multicast network path information to various network nodes in a network environment are disclosed. An exemplary method includes a downstream node transmitting a first message including a network path indicating a specific desired route that is to be used when delivering multicast traffic from a given multicast source to a given host, as well as an identifier assigned to the network path in order to uniquely identify that network path in the network. The method also includes the downstream node transmitting a second message for announcing that the multicast source is to be reached via the network path announced in the first message. The second message identifies the network path to be used by including the identifier of the path announced in the first message, but not the network path itself.

Distributing network path information in a network environment

In one embodiment, a method includes transmitting a packet from a router located in a communication path between a source and a receiver, the packet having one or more values used to select a group designated router from a list of candidate group designated routers for multicast traffic streams, selecting the router as said group designated router for one or more of the multicast traffic streams, and forwarding traffic for the one or more multicast traffic streams to the receiver. The candidate group designated routers are last hop routers for transmitting the multicast traffic streams to a common link connected to the receiver. An apparatus is also disclosed herein.

Protocol independent multicast designated router redundancy

In one embodiment, a method includes identifying a packet at an upstream node in communication with a source and in communication with a downstream node through equal cost multiple paths including first and second multi-access networks, the packet transmitted on the first multi-access network and associated with a multicast group, and transmitting from the upstream node a request to the downstream node to join the group on the second multi-access network, if the upstream node is already transmitting data to the group on the second multi-access network, or a bandwidth utilization at the first multi-access network exceeds a specified threshold. An apparatus is also disclosed.

Bandwidth utilization for equal cost multiple paths

In one embodiment, a first Edge Device may join a multicast group via a multicast router, wherein the first Edge Device is in a local network and the multicast router is in a remote network. The first Edge Device may ascertain an existence of both a first multicast source in the local network and a second multicast source in the remote network. The first Edge Device may select the first multicast source as a multicast source from which to receive multicast data for the multicast group. The first Edge Device may notify the second multicast source in the remote network that the first Edge Device is not interested in receiving multicast data for the multicast group from the second multicast source.

Optimizing OTV multicast traffic flow for site local receivers

In one embodiment, a method includes transmitting a packet from a router located in a communication path between a source and a receiver, the load balancing packet having one or more values used to select a group designated router from a list of candidate group designated routers for multicast traffic streams, selecting the router as said group designated router for one or more of the multicast traffic streams, and forwarding traffic for the one or more multicast traffic streams to the receiver. The candidate group designated routers are last hop routers for transmitting the multicast traffic streams to a common link connected to the receiver. An apparatus is also disclosed.

In one embodiment, a relay device of a network, which is reachable by a source device via only a non-multicast network, receives a non-multicast that encapsulates a multicast message. The relay device is connected to a sub-network of one or more devices. The relay device decapsulates the unicast message to determine the multicast message, re-encapsulates the multicast message as a relay-sourced multicast message, and multicasts the relay-sourced multicast message to the one or more devices within the sub-network.

Multicast data delivery over mixed multicast and non-multicast networks

In one embodiment, a network device may receive an mtrace query, where the mtrace query identifies two or more multicast routing paths. The network device may generate two or more mtrace requests using at least a portion of information obtained from the mtrace query such that each of the two or more mtrace requests identifies a different one of the two or more multicast routing paths. The network device may send each of the two or more mtrace requests via a different one of the two or more multicast routing paths. The network device may then receive at least one response including information pertaining to the two or more multicast routing paths.

Enhancing mtrace to detect failure in multicast diverse paths

In one embodiment, a first Edge Device may join a multicast group via a multicast router, wherein the first Edge device is in a first site of a network and the multicast router is in a second site of the network. The first Edge Device may ascertain an existence of both a first multicast source in the first site of the network and a second multicast source in the second site of the network. The first Edge Device may select the first multicast source as a multicast source from which to receive multicast data for the multicast group. The first Edge Device may notify the second multicast source in the second site of the network that the first Edge Device is not interested in receiving multicast data for the multicast group from the second multicast source.

A method is provided in one example and includes evaluating multiple paths in a network in order to execute a reverse path forwarding decision for multicast traffic associated with a source. The method may also include selecting a second network path based on a first network path previously been designated as a route for the multicast traffic associated with the source. The first network path and a second network path differ by at least one network element. The method further includes receiving at least one of a first data stream and a second data stream, wherein the first data stream is associated with the first network path and the second data stream is associated with the second network path.

System and method for providing a path avoidance feature in a network environment

In one embodiment, a method includes receiving a join message from a receiver at a receiver edge router, the join message identifying a source and a group, and creating at least two forwarding trees for transmitting multicast data streams comprising duplicate data to the receiver edge router. The forwarding trees include a root at a source edge router in communication with the source, and different network paths. The method further includes receiving a packet from one of the forwarding trees and processing the received packet to determine if the packet is a duplicate of another packet received at the receiver edge router. If the packet is a duplicate packet, it is discarded. If the packet is not a duplicate, it is forwarded to the receiver. An apparatus is also disclosed.

Network based multicast stream duplication and merging

A method, system, apparatus and machine-readable medium for transmitting a packet through a network to convey network topology is provided. The method includes the step of generating at least one link state protocol data unit (LSP) with a first identifier until reaching a maximum sequence number in a sequence assigned to a network device, represented by the first identifier. The method further includes the step of modifying the first identifier to produce a second identifier. The method also includes the step of generating at least one LSP with the second identifier, and with a sequence number that is less than or equal to the maximum sequence number in the sequence. The system for transmitting a packet through a network, to convey network topology, comprises the means for performing the above-mentioned method steps.

Method and system to restart IS-IS when LSP wraps

Disclosed are methods and apparatus for flooding link state packets or packet data units (LSP's) from a first node to one other LSP receiving node, where the LSP's are flooded in an order that is related to relative costs of various paths emanating from the first node. That is, the first node sends its own LSP first since the first node has no cost relative to itself. The first node then sends other LSP's that are associated with a plurality of other LSP sending nodes that have previously flooded their LSP's to the first node. These other LSP's are sent by the first node to the other LSP receiving node in an order related to the relative costs associated with the paths from the first node to each of the other LSP sending nodes which had previously sent the other LSP's to the first node.

Method and apparatus for flooding link state packets to achieve faster convergence

Methods, systems, and apparatuses for transmitting link state packet (LSP) through a network are provided. The method includes dividing the LSP into LSP fragments having respective fragment numbers, transmitting the LSP fragments repetitively through the network, identifying at least one LSP fragment that is updated while the LSP fragments are being transmitted, and retransmitting the identified LSP fragments. The transmitted updated LSP is used for processing the Shortest Path First algorithm to identify accurately the shortest path that can be used to establish communication in the network.

Method and system for transmitting LSP fragments

Disclosed are methods and apparatus for flooding link state packets or packet data units (LSP's) from a first node to one other LSP receiving node, where the LSP's are flooded in an order that is related to relative costs of various paths emanating from the first node. That is, the first node sends its own LSP first since the first node has no cost relative to itself. The first node then sends other LSP's that are associated with a plurality of other LSP sending nodes that have previously flooded their LSP's to the first node, and these other LSP's are sent by the first node to the other LSP receiving node in an order related to the relative costs associated with the paths from the first node to each of the other LSP sending nodes which had previously sent the other LSP's to the first node.

Disclosed are methods and apparatus for handling Link State Packets (LSPs) sent between processing nodes within a computer network. At a first node, an LSP sent by a second node is received. The received LSP specifies connectivity information regarding the second node. It is then determined whether one of two conditions is met: either the received LSP is an updated LSP even though it appears older and a corresponding stored LSP fails authentication, or the received LSP fails authentication and it appears newer. If it is determined that one of these conditions is met, as well as purging criteria, then updating procedures are then performed on the LSP information that is maintained by the first node, where the LSP information was originally obtained from a corresponding LSP sent by the second node.

Growing community of inventors

San Jose, CA, United States of America

Heidi H Ou