US 12,452,158 B2
Stitching a segment routing (SR) policy to a local SR policy for routing through a downstream SR domain
Divya Bhargava, San Jose, CA (US); Muthurajah Sivabalan, Ottawa (CA); and Arif Aboobacker, San Jose, CA (US)
Assigned to Ciena Corporation, Hanover, MD (US)
Filed by Ciena Corporation, Hanover, MD (US)
Filed on Feb. 18, 2022, as Appl. No. 17/675,271.
Prior Publication US 2023/0269167 A1, Aug. 24, 2023
Int. Cl. H04L 45/02 (2022.01); H04L 45/12 (2022.01)
CPC H04L 45/04 (2013.01) [H04L 45/02 (2013.01); H04L 45/123 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A Network Element (NE) arranged in an upstream domain of a network, the NE comprising:
a processing device,
a database, and
a memory device configured to store a computer program having instructions that, when executed, enable the processing device to
obtain, via an advertisement, a Segment Routing (SR) policy including a Binding Segment Identifier (BSID) for routing a packet along a path in a downstream domain, the SR policy including at least a destination field and a color field, the destination field defining an end-point of the path in the downstream domain, the end-point representing a destination node or service instance, the color field defining the path in the downstream domain, and
store the SR policy including the BSID in the database,
wherein the SR policy is for the downstream domain, separate from the upstream domain with the NE, wherein status of the downstream domain is unknown to the NE in the upstream domain, and wherein the advertisement includes the SR policy and the BSID associated therewith, and wherein the NE is a device located in the upstream domain and the NE uses the SR policy for the downstream domain to stitch SR policies between the upstream domain and the downstream domain without assistance from a higher level controller having knowledge of the NE and the downstream domain, and without a Path Computation Engine (PCE) configured to compute paths spanning across multiple Interior Gateway Protocol (IGP) areas or level.