Nortel Networks Corporation

Rockstar Consortium US LP

Ciena Corporation

Rockstar Bidco, LP

Rpx Clearinghouse LLC

Northern Telecom Limited

Cambridge Consultants Limited

Constellation Technologies, LLC

Cieno Corporation

Rockstart Bidco, LP

Ciena Luxembourg S.a.r.l.

Nigel Lawrence Bragg

David Allan

Jerome Chiabaut

Robert Friskney

Simon P Parry

Peter Ashwood Smith

Paul Unbehagen

Peter J Ashwood-Smith

Clive Colin Hayball

Simon Daniel Brueckheimer

Marc Holness

Ian Hamish Duncan

Liam M Casey

Guoli Yin

Gerard Leo Swinkels

Hong Zhang

Mohnish Anumala

Roger Lapuh

Paul Allen Bottorff

Malcolm Betts

Robert William Young

Julian Frank Cable

Niall Forbes Ross

Bram Peeters

Philip Davies

Bruno Germain

James Andrew Bangham

Paul Ungehagen

Peter Jamieson Tattersfield

Alan Frank Graves

Darek Robert Skalecki

Dinesh Mohan

Alan Robinson

Gerald Smallegange

Nigel Baker

Michael Suiping Chen

John J Osswald

Martin Biddiscombe

Stephen C Lewis

Andrew J Tunnicliffe

Hadi Nasrallah

Ross M MacGillivray

Yin Guoli

Douglas Fisher

Gordon Bradley

Adnanus Henricus Nicolaas Roestenburg

Preben Hunnerup

Peter Jamieson Tatterfield

David Allen

Jérôme Chiabaut

Mirza Arifovic

Michael Chen

A multicast method for Segment Routing includes, in a Segment Routing network with a plurality of nodes, wherein Segment Routing utilizes globally significant labels as node identifiers such that path state installation is only required at an ingress node of a Segment Routing domain, advertising a multicast flow by a source node; determining roles in the multicast flow for the plurality of nodes; and installing appropriate forwarding behavior for the multicast flow at the plurality of nodes based on the determined roles. The advertising can utilize Interior Gateway Protocol (IGP). For the multicast flow, source node segments are used to construct source routed trees rather than destination-based paths, wherein the source routed trees define broadcast paths, versus destination-based paths which are used in Segment Routing to define a node segment.

Multicast systems and methods for segment routing

Multicast systems and methods for Segment Routing include receiving, at a node, a multicast packet including an outer label comprising a Multiprotocol Label Switching (MPLS) source node identifier defining a source-rooted broadcast tree and an inner label including a service identifier defining a service specific multicast tree; responsive to the node including a branch point on the source-rooted broadcast tree, popping the outer label, analyzing the inner label to identify active egress ports, pushing back the outer label, and forwarding the multicast packet to the active egress ports; and responsive to the node including point-to-point transit for the source-rooted broadcast tree, forwarding the multicast packet on the source-rooted broadcast tree.

Interest in multicast group membership may be advertised via a routing system on an Ethernet network along with an indication of an algorithm to be used by the nodes on the network to calculate the distribution tree or trees for the multicast. Each node, upon receipt of the advertisement, will determine the algorithm that is to be used to produce the multicast tree and will use the algorithm to calculate whether it is on a path between nodes advertising common interest in the multicast. Example algorithms may include shortest path algorithms and spanning tree algorithms. This allows multicast membership to be managed via the routing control plane, while enabling spanning tree processes to be used to forward multicast traffic. Since spanning tree is able to install multicast state per service rather than per source per service, this reduces the amount of forwarding state required to implement multicasts on the routed Ethernet mesh network.

Method and apparatus for multicast implementation in a network

A method for validation of a packet transport network includes performing a header space analysis, with input headers to obtain output headers from the header space analysis, between one or more ingress points and a particular egress point; determining disjointness of the output headers; and determining validity of a point-to-point connection property of the packet transport network based on the disjointness of the output headers. The header space analysis allows near-real-time validation that packet transport flows in an Multiprotocol Label Switching-Transport Profile (MPLS-TP) network have been correctly programmed on the switches by a Software Defined Networking (SDN) controller or other technique such that the correct label mappings have been made to carry a flow from a source to a destination, and all flows from any source to a destination are isolated from one another.

Header space analysis extension systems and methods for transport networks

Embodiments of the disclosure are directed to implementing a router Media Access Control (MAC) Ethernet switch in a network. An Ethernet-over-Dense Wave Division Multiplexing (DWDM) packet switch system includes a transport switching element communicatively coupled to one or more routers in a client layer and communicatively coupled via a photonic switching layer with a plurality of transport switching elements forming a transport layer; wherein the transport switching element is configured to flood addresses, in the transport layer, associated with the one or more routers to disseminate learned end-point addresses of the one or more routers so that service-based addressing is resolved by the transport layer. The addresses from the client layer are flooded in the control plane which is a lower layer control plane relative to the client layer to allow the transport switching element and the plurality of transport switching elements to use of the addresses.

Network-based ethernet switching packet switch, network, and method

A method and apparatus for diverting traffic in a communications network are disclosed. According to one aspect, the invention provides a communications network with a first node and a second node. Connecting these two nodes is a first set of intermediate nodes on a first path (the true shortest path) and a second set of intermediate nodes on a second alternate path. At a first node, a first processor determines whether a packet arriving at the first node must transit the second node. If so, the base virtual local area network (VLAN) identifier (VID) of the packet is replaced by a first VID, and the packet is transmitted along the second path through the second set of intermediate nodes to the second node. At the second node, a second processor determines whether a packet arriving at the second node must transit the first node. If so, the base VID of the packet is replaced by a second VID different from the first VID and different from the base VID, and the packet is transmitted along the second path through the second set of intermediate nodes to the first node.

Method and apparatus for traffic engineering in shortest path bridged networks

Method and apparatus for multicast implementation in a routed ethernet mesh network

Nodes on an Ethernet network run a link state protocol on the control plane and install shortest path forwarding state into their FIBs to allow packets to follow shortest paths through the network without requiring MAC header replacement at each hop through the network. When a node learns an IP address, it will insert the IP address into its link state advertisement to advertise reachability of the IP address to the other nodes on the network. Each node will add this IP address to its link state database. If a packet arrives at an ingress node, the ingress node will read the IP address, determine which node on the link state protocol controlled Ethernet network is aware of the IP address, and construct a MAC header to forward the packet to the correct node. The DA/VID of the MAC header is the nodal MAC of the node that advertised the IP address. Unicast and multicast IP forwarding may be implemented.

IP forwarding across a link state protocol controlled ethernet network

The invention relates to enabling differential forwarding in address-based carrier networks such as Ethernet networks. There is described a method of and connection controller for establishing connections () in a frame-based communications network comprising nodes (-and) such as Ethernet switches. The connections are established by configuring, in various of the nodes, mappings for forwarding data frames, such as Ethernet frames. The mappings are from a combination of a) a destination (or source) address corresponding to a destination (or source) node () of the connection and b) an identifier, such as a VLAN tag. The mappings are to selected output ports of the various nodes. By using the combination of destination (or source) address AND identifier, the mappings enable data frames belonging to different connections () to be forwarded differentially (ie forwarded on different output ports) at a node () despite the different connections having the same destination node. This enables flexibility in routing connections and the ability to perform traffic engineering.

Differential forwarding in address-based carrier networks

A source Multiprotocol Label Switching (MPLS) network element, a destination MPLS network element, and a MPLS method are disclosed which introduce the concept of a source label into the MPLS label stack for source identification preservation. The source label can located at the bottom of the label stack thereby being a last item popped in the MPLS stack at the destination node, or indicated subsequent to an explicit reserved label identifier. The source label is used for maintaining Operations, Administration, and Maintenance (OAM) data efficiently without requiring deep packet inspection.

Source identification preservation in multiprotocol label switching networks

A resilient virtual Ethernet ring has nodes interconnected by working and protection paths. Each node has a set of VLAN IDs (VIDs) for tagging traffic entering the ring by identifying the ingress node and whether the traffic is on the working or protection path. MAC addresses are learned in one direction around the ring. A port aliasing module records in a forwarding table a port direction opposite to a learned port direction. Each node can also cross-connect working and protection paths. If a span fails, the two nodes immediately on either side of the failure are cross-connected to fold the ring. Working-path traffic is cross-connected onto the protection path at the first of the two nodes and is then cross-connected back onto the working path at the second of the two nodes so that traffic always ingresses and egresses the ring from the working path.

Q-in-Q Ethernet rings

Embodiments of the disclosure are directed to implementing a router Media Access Control (MAC) Ethernet switch in a network. An embodiment receives, from a first Multiprotocol Label Switching (MPLS) router, at least one data packet with a router MAC address identifying a second MPLS router; automatically learns the router MAC address identifying the second MPLS router; accesses information to determine the Internet Protocol (IP) address of the second MPLS router based on the learned router MAC address; and transmits the at least one data packet to the second MPLS router.

Method and system for traffic engineered MPLS ethernet switch

Network protection between endpoints includes both end-to-end and local section protection. A primary path between the endpoints includes a plurality of links, and is protected on an end-to-end basis by a protection path associated with different links. At least one sections of the primary path is also protected on a local basis, where a 'section' is a link, ring, trunk or other portion of a network. One or more sections of the protection path may also be protected on a local basis. In response to detection of a fault condition, section protection is utilized to overcome the fault if possible, and otherwise end-to-end protection is utilized. Invoking section protection does not imply a switchover from the primary end-to-end path to the protection end-to-end path. Rather, the primary end-to-end path is rerouted in the affected section.

Protection for provider backbone bridge traffic engineering

A method of managing traffic flow in a packet network. A working sub-network is provided, which comprises one or more provisioned static working paths between at least one source node and one or more destination nodes in the network, and the working sub-network with a service instance. A backup sub-network is provided, which comprises one or more dynamic protection paths between the at least one source node and the one or more destination nodes, and the backup sub-network associated with the service instance. During a normal operation of the network, forwarding subscriber traffic associated with the service instance through the network using the working sub-network. Following detection of a network failure affecting the service instance, the subscriber traffic associated with the service instance is switched for forwarding through the network using the backup sub-network.

Provisioned provider link state bridging (PLSB) with routed back-up

A method of peer interfacing a Link-State controlled network domain with an Ethernet Bridging controlled network domain. A pair of peer attachment points are provided between the Link-State controlled network domain and the Ethernet Bridging domain. The peer attachment points are respective endpoints of a set of one or more LAN segments defined within the Ethernet Bridging domain. The set of LAN segments are represented as a virtual node in the Link-State controlled network domain. The virtual node is represented in the Link-State controlled network domain as connected to each of the peer attachment points via a respective virtual link. The virtual links are configured such that frames to or from an address in the Link-State controlled network domain are forwarded over a tree passing through only one of the peer attachments points.

Resilient provider link state bridging (PLSB) virtual private LAN service (VPLS) interworking

Growing community of inventors

Weston Colville, United Kingdom

Nigel Lawrence Bragg