Ciena Corporation

Himanshu Shah

Sami Boutros

Peng He

Muthurajah Sivabalan

Jayant Kumar Bhardwaj

Marc Holness

Cengiz Alaettinoglu

Amal Karboubi

Siva Sivabalan

Atul Vadera

Darek Robert Skalecki

Ronald Mark Parker

Mark Libby

Gerald Smallegange

Piyush Sharma

Ashwath Narasimhan

Divya Bhargava

Arif Aboobacker

Thor Odd Andres Ramsland

David Parks

Andrew Walker

Prabhakar Nagral

Dennis E Hayes

Selvamani Ramasamy

A node, in a first network, includes circuitry configured to determine a next hop as decided by Border Gateway Protocol (BGP) is an anycast prefix to a Route Reflector (RR) interconnecting the first network with a second network, responsive to the next hop being the anycast prefix to the RR, create a tunnel with a destination based on the anycast prefix, and utilize the tunnel for traffic having the next hop as the anycast prefix to the RR. The anycast prefix is assigned to two or more RRs interconnecting the first network and the second network. A first path is decided by BGP based on a BGP Path Selection Algorithm that is independent of a second path determined by Interior Gateway Protocol (IGP). The first path and the second path can be different, and wherein tunnel is utilized to ensure the traffic always follows the first path.

BGP LU resiliency using an anycast SID and BGP driven anycast path selection

Variable preemption for label-switched paths (LSP) tunnels includes provisioning a label-switched path (LSP) tunnel at a first bandwidth with a first priority value; and provisioning one or more different priority values at one or more of (1) corresponding one or more bandwidths such that a current priority value of the LSP tunnel is set based on a current bandwidth value of the LSP tunnel and (2) redial failure attempts such that the current priority value of the LSP tunnel is set based on a number of the redial failure attempts. The priority values can include one of a Setup Priority, a Holding Priority, and a combination thereof. The one of the Setup Priority, the Holding Priority, and the combination thereof can be based on RFC 3209.

Variable preemption for LSP tunnels

Systems and methods associated with a node in a Segment Routing network include, responsive to what services are support at a node in a Segment Routing network, creating a bitmap to represent the plurality of services supported at the node; and transmitting an advertisement with the bitmap such that the advertisement is a single advertisement of multiple services. This approach can reduce the advertisement of rout updates by orders of magnitude.

Bitmap signaling of services using segment routing

Systems and methods implemented in a network element in a Segment Routing network include, for a service having two or more candidate paths and responsive to a failure on a current candidate path of the two or more candidate paths, setting an eligibility flag for the current candidate path; and selecting another candidate path of the two or more candidate paths, for the service, based on their eligibility flag.

Emulating MPLS-TP behavior with non-revertive candidate paths in Segment Routing

A node in a Segment Routing network includes circuitry configured to signal first service Segment Identifiers (SIDs), for one or more first Ethernet services configured at the node, to other nodes in the Segment Routing network, receive second service SIDs for one or more second Ethernet services configured at the other nodes in the Segment Routing network, and configure the second service SIDs for one or more second Ethernet services. The first service SIDs and the second service SIDs can be signaled by one of Interior Gateway Protocol (IGP) and Border Gateway Protocol (BGP).

Ethernet services with segment routing with dataplane MAC learning

A method implemented in a network element includes, for a service, receiving a Segment Identifier (SID) list and an explicit list for an intended path in a Segment Routing network; expanding the SID list and comparing the expanded SID list to the explicit list; and setting the intended path as either valid or invalid based on the comparing. The intended path can be a primary path, and the steps can further include receiving a SID list and an explicit list for a backup path in the Segment Routing network. The steps can further include switching to the backup path responsive to a failure on the primary path, and switching back to the primary path responsive to it being valid.

Handling diversity constraints with Segment Routing and centralized PCE

Systems and methods for extending Ethernet Virtual Private Network (EVPN) protocols are provided. A Link Aggregation Group (LAG), according to one implementation, includes a plurality of Ethernet Segments (ESs) and a plurality of service ports configured to communicate over the plurality of ESs. The service ports are configured to enable an operator device to access an EVPN to receive Layer 2 (L2) and Layer 3 (L3) Ethernet services. Also, the service ports are configured to enable the operator device to operate with multi-homing functionality to receive the L2 and L3 Ethernet services via redundant paths associated with the plurality of ESs. The services ports are further configured to respond to operator commands, whereby the operator commands include one or more operator commands related to switching among the redundant paths.

Responding to operator commands in a multi-homing ethernet virtual private network (EVPN)

Systems and methods include obtaining a plurality of services supported at the node; determining a bitmask to represent the plurality of services supported at the node, wherein the bitmask includes a starting service and each subsequent bit representing another service of the plurality of services and with each bit in the bitmask set based on the plurality of services supported at the node; and transmitting an advertisement to nodes in the Segment Routing network with a starting Service SID value and the bitmask based on the plurality of services supported at the node. The plurality of services can include any of a Virtual Private Wire Service (VPWS) and a Flexible Cross Connect (FXC) service.

VPWS signaling using segment routing

Systems and methods include obtaining a table having a plurality of addresses each having a plurality of attributes and classifications; responsive to a requirement to reduce a size of the table, reducing a number of the plurality of addresses based on one or more reduction approaches that use any of the plurality of attributes and classifications; and obtaining an output table having some or all of the plurality of addresses for a table receiver. The table can be obtained via control plane components including one or more of Interior Gateway Protocol (IGP) and Border Gateway Protocol (BGP). The requirement to reduce the size is based on a size of the table and a size of memory associated with the table receiver.

Controlling routing behavior during router table-memory exhaustion events

A node, in a first network, includes circuitry configured to add a label stack to a packet associated with one of a Layer 2 Virtual Private Network (L2VPN) and a Layer 3 Virtual Private Network (L3VPN), wherein the packet is destined for a second network having at least a pair of Border Gateway Protocol-Label Unicast (BGP-LU) Route Reflector (RR) nodes interconnecting the first network, and wherein the label stack includes an anycast Segment Identifier (SID) for the RR nodes, in Segment Routing, and transmit the packet to the second network. The label stack also includes a BGP-LU label for a destination in the second network. Responsive to isolation of one of the RR nodes, a Point of Local Repair (PLR) node in the first network is configured to implement Topology-Independent Loop-Free Alternate (TI-LFA) for the anycast SID.

Bgp Lu resiliency using an anycast SID and BGP driven anycast path selection

A node in a Segment Routing network includes a plurality of ports and a switching fabric between the plurality of ports, wherein, for an Ethernet Tree (E-tree) service, a port is configured to transmit a packet with a plurality of Segment Identifiers (SID) including a first SID, a second SID, and a third SID, wherein the first SID identifies one of multicast, ingress replication for broadcast, and a destination node including any of a node SID and an anycast SID, wherein the second SID identifies a service including the E-tree service, and wherein the third SID identifies a source of the packet. A second port of the node is connected to a customer edge, and wherein the third SID is based on whether the customer edge is a leaf node or a root node in the E-tree service.

NG-VPLS E-tree signaling using segment routing

A network element includes a plurality of ports interconnected by a switching fabric, wherein a port includes a plurality of connections including an infrastructure connection that operates a Bidirectional Forwarding Detection (BFD) session and a group of connections that share a similar fate for a fault as the infrastructure connection; and a controller configured to detect a fault on the infrastructure connection via the BFD session, and cause a protection switch for one or more of the group of connections based on the fault on the infrastructure connection. The infrastructure connection and the group of connections can be Pseudowires (PWE) or Label Switched Paths (LSPs) in a Multiprotocol Label Switching (MPLS) network.

Pseudowire and label switched path grouping to achieve scale in protection switching

Systems and methods include receiving one or more Ethernet Virtual Private Network (EVPN) advertisements from one or more peer nodes with information including any of traffic characterization information and traffic control information; and providing traffic to the EVPN and to the corresponding one or more peer nodes based on the information from the corresponding one or more peer nodes. The one or more EVPN advertisements can be in an EVPN Network Layer Reachability Information (NLRI) advertisement, and the EVPN NLRI can have Route Type 1 for the information to apply to an EVPN Instance (EVI) and the EVPN NLRI can have Route Type 2 for the information to apply to a specific customer node based on a Media Access Control (MAC).

Flexible traffic control for EVPN

A node in a Segment Routing network includes a plurality of ports and a switching fabric between the plurality of ports, wherein, for an Ethernet Virtual Private Network (EVPN)-Virtual Private Local Area Network Service (VPLS), a port is configured to transmit a packet with a plurality of Segment Identifiers (SID) including a destination SID that identifies a destination node of the packet, a service SID that identifies an EVPN Instance (EVI), and a source SID that identifies one of the node and an Ethernet Segment (ES) that includes the node. The port can be further configured to receive a second packet with a second plurality of SIDs, and learn a Media Access Control (MAC) address based on a second service SID and a second source SID, of the second packet.

EVPN signaling using segment routing

Systems and methods for inducing a recovery of a service along a shorter path are provided. In one embodiment, a system having a processing device and a memory device is disclosed. The memory device is configured to store software logic including instruction that, when executed, enable the processing device to determine there is a defect in a primary Segment Routing (SR) to a main destination. The instructions further enable the processing device to identify an available path to an alternative destination that is shorter than a backup SR path to the main destination. Also, a main service associated with the main destination is switched over to an alternative service associated with the alternative destination based on the determining and the identifying.

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Hopkinton, MA, United States of America

Himanshu Shah