Fast re-route for optical networks

摘要

An optical network device re-routes traffic from a path to a backup path in response to determining that a downstream segment of the primary path is not operational. The optical network device receives traffic on a slot of an optical fiber. For each data unit in the traffic, the optical network device determines, based on receiving the data unit on the slot and based on a flow identifier specified in the data unit, that a given path is associated with the data unit. If a downstream segment of the given path is not operational, the optical network device routes the data unit onto a backup path instead of routing the data unit along the given path. Bandwidth is not reserved for the backup path.

主权项

1. A method comprising:
receiving, at an optical network device, traffic on a physical slot of a first optical fiber, the first optical fiber connected to a first port of the optical network device, the traffic including a given data unit; identifying, by the optical network device based on the given data unit being received on the physical slot of the first optical fiber and based on a flow identifier specified by the given data unit, a forwarding table entry associated with a first path,
wherein the forwarding table entry includes a primary downstream port identifier, a backup downstream port identifier, a primary downstream slot identifier, and a backup downstream slot identifier, the backup downstream port identifier identifying a port of the optical network device that is connected to a second optical fiber, the primary downstream port identifier identifying a port of the optical network device that is connected to a third optical fiber, the primary downstream slot identifier identifying a slot of the third optical fiber, the backup downstream slot identifier identifying a virtual slot of the second optical fiber, the virtual slot of the second optical fiber reserved for a second path; determining whether a downstream segment of the first path is operational; and in response to determining that the downstream segment of the first path is not operational:
identifying, based on the virtual slot of the second optical fiber, a physical slot of the second optical fiber; andforwarding the given data unit on the physical slot of the second optical fiber.