Cisco Technology, Inc.

Gargi Nalawade

David Delano Ward

Keyur Patel

Stefano Benedetto Previdi

Stewart Frederick Bryant

Clarence Filsfils

Himanshu H Shah

Robert Raszuk

Mike Shand

John Galen Scudder

Ruchi D Kapoor

James Neil Guichard

John Harper

Ian Michael Charles Shand

Chandrashekhar Appanna

Luca Martini

Steven Vincent Luong

David Alexander Ball

Olivier Bonaventure

Mukhtiar Shaikh

Martin Djernaes

Barry Friedman

Muhammad Ahmed Moizuddin

Shyam Suri

Pierre Francois

Sandy Ng

A method and apparatus for providing multicast messages across a data communication network, the method comprising the computer-implemented steps of: receiving a multicast join message; adding to the multicast join message a next hop and an address of a router to which the multicast message is to be sent; forwarding the multicast message based on the next hop address.

Method and apparatus for providing multicast messages within a virtual private network across a data communication network

A method is disclosed for advertising update messages to peers and peer entities. In an embodiment, all update messages that are to be advertised to a specific peer entity are formatted and enqueued to a peer associated with that peer entity before update messages are formatted for another peer entity. In an aspect, the method advertises update messages to peer entities in a communication network comprises, among a quantity of update messages, formatting one or more of the update messages to establish a quantity of formatted update messages for a peer entity, wherein said peer entity is one of a peer group and a peer, wherein the quantity of the formatted update messages is less than or equal to the quantity of update messages, and among the formatted update messages, enqueueing to a queue, one or more formatted update messages, to establish a quantity of enqueued formatted update messages, wherein the quantity of enqueued formatted update messages is less or equal to the quantity of formatted update messages, and wherein at least one of the quantity of formatted update messages and the quantity of the enqueued formatted update messages is a programmable quantity.

Method and apparatus for advertising update messages to peers and peer groups in a border gateway protocol process

An apparatus and method as described for constructing a repair path for use in the event of failure of an inter-routing domain connection between respective components in first and second routing domains of a data communications network. The apparatus is arranged to assign a propagatable repair address for use in the event of failure of the inter-routing domain connection and to propagate the repair address via data communications network components other than the inter-routing domain connection.

Constructing a repair path in the event of failure of an inter-routing domain system link

An arrangement for scheduling scans of internal network nodes for reachability events by a border node of a network domain, schedules the scans according to the rate at which reachability notifications are received by the node. As the rate at which notifications are received increases, the interval between scans also increases. Conversely, as the rate of notifications decreases, the interval also decreases.

System for scheduling scans of interior nodes of a network domain for reachability events

An apparatus for providing reachability in a routing domain of a data communications network having as components nodes and links therebetween for a routing domain external destination address is provided. The apparatus is arranged to advertise destination address reachability internally to nodes in the routing domain and associate a reachability category with the internal advertisement of the destination address reachability.

Providing reachability information in a routing domain of an external destination address in a data communications network

A method of constructing a backup path in an autonomous system (AS) for failure of an inter-AS link is described. The method comprises identifying an alternate inter-AS path and constructing a tunnel to an end point on the alternate path.

Method of constructing a backup path in an autonomous system

A method, apparatus and computer program product for providing Outbound Route Filtering (ORF) is presented. An ORF list is produced and an ORF filter is built from the ORF list. The ORF list is built from received ORF entries. The ORF list is advertised to client and non-client peers. The ORF filter is built from a received ORF list and is directed toward the advertiser of the ORF list.

Automatic ORF-list creation for route partitioning across BGP route reflectors

A method is disclosed for routing BGP traffic. In one embodiment, according to the method, an association is formed between a first process and a second process. The first process includes a first BGP process on a first peer and the second process includes a second BGP process on a second peer. The association is formed using a reliable datagram-oriented IP transport protocol. Traffic sent from the first BGP process is segregated into a control traffic type and an update traffic type and any more finer classifications that can further classify BGP traffic. The traffic from the first BGP process is sent to the second BGP process in accordance with a priority allocation assigned to the traffic types based on the association.

QoS and fault isolation in BGP traffic, address families and routing topologies

In a link state protocol such as an interior gateway protocol (IGP), link state advertisements or link state packets (LSA/LSPs) are sent only to network nodes that have expressed interest in them, rather than always flooding them.

Selectively sending link state messages in a network link state protocol based on interest of network nodes

In one embodiment, an apparatus and method are described for constructing a repair path in the event of non-availability of a routing domain component of a routing domain comprising, as components, links and nodes. The apparatus is arranged to receive respective network repair addresses from each of the far-side and near-side advertising node for use in the event of non-availability of a routing domain component between the advertising node. The apparatus is further arranged to advertise the near-side advertising node network repair address to one or more far-side nodes via a path external to the routing domain.

Constructing a repair path in the event of non-availability of a routing domain

A network data packet routing apparatus with BGP is configured to soft reset an AFI or SAFI, so that forwarding on routes associated with the AFI or SAFI can continue even after an event or error. One approach involves establishing a Border Gateway Protocol (BGP) peering session between a first node and a second node in a packet-switched network; detecting a BGP condition requiring a reset of a BGP address family indicator (AFI) data structure or a sub-address family indicator (SAFI) data structure, wherein the BGP condition does not affect states of routes in the AFI or SAFI; preserving a BGP state and a forwarding state of the AFI or SAFI; and forwarding data on routes represented in the AFI or SAFI. Soft notification messaging and marking routes as stale facilitates the approach.

Network routing apparatus that performs soft graceful restart

A soft notification technique isolates address family application based errors or events occurring within a routing protocol, such as the Border Gateway Protocol (BGP), used to exchange routing information between a router and its peer router over a BGP session operating on a reliable transport. The technique apportions the session into a plurality of logical subsets, each of which is associated with an address family application (AFI/SAFI) module of a BGP protocol executing on the routers. BGP soft notification messaging is employed to allow the router to notify its peer of an isolated error condition or event associated with an AFI/SAFI module. Isolation of the error/event enables restart ('soft reset') of only the associated AFI/SAFI module, thereby obviating the need to reset or terminate the entire BGP session and reliable transport between the router and peer. Notably, soft reset of the module occurs without disrupting services provided by other AFI/SAFI modules of the BGP protocol.

Soft notification messaging for a routing protocol

Methods and apparatus for efficiently enabling routing states to be recovered after a failover or during a software upgrade in a system which supports graceful restart and stateful switchover are disclosed. According to one aspect of the present invention, a method for restarting a network device which has a plurality of routers and is in communication with a first peer being arranged to support graceful restart and a second peer includes performing a graceful restart with respect to the first peer. A peer transparent failover is performed with respect to the second peer. The graceful restart and the peer transparent failover are performed in response to a failure associated with the network device.

Routing system and method for transparently rocovering routing states after a failover or during a software upgrade

A method for border nodes using the Border Gateway Protocol to advertise path updates to peer nodes in other domains involves calculating the update interval for each advertisement of an update of the same path to the same peer and advertising the update when the interval has expired. The update interval is the sum of the standard update interval and the unexpired portions of update intervals applied to previous unadvertised updates.

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San Jose, CA, United States of America

Gargi Nalawade