Cisco Technology, Inc.

Nagendra Kumar

Carlos M Pignataro

Clarence Filsfils

Pierre Jean Rene Francois

Ijsbrand Wijnands

Stefano Benedetto Previdi

Rajiv Asati

George Swallow

Ahmed Refaat Bashandy

Nobushige Akiya

A receiving node receives a virtual LDP initialization (vInit) message from a first node, where the vInit message comprises a request to establish a vLDP session between a requesting node and a target node. If the receiving node does not own a destination address of the vInit message, the receiving node is determined to be a relay node. The relay node inserts a relay label into the vInit message, where the relay label is an outgoing label that the relay node uses to reach the first node, and forwards the vInit message toward the destination address. If the receiving node owns the destination address, the receiving node is determined to be the target node, which extracts a stack of relay labels from the vInit message. The relay labels are used to define a return path to the requesting node for messages transmitted over the vLDP session.

Virtual LDP Session

In one embodiment, a method comprises generating, by a first provider edge router associated with a first segment identifier, a primary label for reaching a destination, and repair information for reaching the destination if a second provider edge router is unavailable to reach the destination; allocating, by the first provider edge router, a first protected next-hop address associated with the first segment identifier for protected reachability to at least the destination; and sending via a core network, by the first provider edge router, an advertisement specifying the label and the repair information, enabling an ingress provider edge router to insert, into a data packet destined for the destination, the labels from the first provider edge router and the second provider edge router based on the repair information, for fast rerouting to the destination via one of the first or second provider edge router if the other is unavailable.

Scalable edge node protection using segment routing

In one embodiment, a method comprises selecting, by an ingress provider edge router, one of first or second provider edge routers as a primary router for reaching a destination via a core network, and selecting the other of the first or second provider edge routers as a backup router for reaching the destination via the core network; and inserting, into an IPv6 data packet destined for the destination, a primary label assigned by the primary router and a repair label assigned by backup router, and an IPv6 extension header specifying first and second segment identifiers associated with the respective first and second provider edge routers and a protected flag that enables fast rerouting of the IPv6 data packet to the backup router if the primary router is unavailable.

Scalable edge node protection using IPv6 segment routing extension header

The present disclosure provides for carrying downstream mapping information in an echo request message and/or echo reply message, which can describe both IP (Internet Protocol) multipath information and label multipath information. A transit node (e.g., an LSR element) that receives an echo request message from an initiator node determines downstream mapping information, which is returned to the initiator node. Transit node determines whether a newly defined type of multipath information (type 10) should be generated to return the downstream mapping information, based on whether transit node performs load balancing based on labels or IP header information, and whether transit node imposes entropy labels. A multipath information type 10 element includes either IP multipath information or label multipath information, as well as associated label multipath information that includes one or more entropy labels that map to the IP or label multipath information being returned.

LSP ping/trace over MPLS networks using entropy labels

A method is provided in one example and includes communicating a first request message to a first network element functioning as a point of local repair for a backup label switched path. The first request message includes a first network address having a predetermined value and an indication of a forwarding equivalence class associated with the backup label switched path. The method further includes receiving a first reply message from the first network element. The first reply message includes at least one backup path parameter associated with the backup label switched path.

Growing community of inventors

Durham, NC, United States of America

Nagendra Kumar