Patent ID: 9438508
Filing Date: 2016-09-06
CPC Classification: H04L

Claim Text:
1. A method comprising: receiving, by a path computation element, topology information for a base network layer of a multi-topology network, the multi-topology network comprising the base network layer having a plurality of network switches interconnected by base network layer three (L3) links in a base network topology and also comprising an overlay network layer having a plurality of overlay switches interconnected by overlay network links in an overlay network topology; receiving, by the path computation element from a client and via a client interface, a path request that specifies two endpoints, a start time for path activation, and a requested bandwidth; computing, by the path computation element in response to receiving the path request and using the topology information for the base network layer and the topology information for the overlay network layer, a path to transport network traffic between the two endpoints; by the path computation element and after computing the path to transport network traffic between the two endpoints, receiving additional topology information for one of the overlay network layer and the base network layer; and sending, by the path computation element to the client via the client interface and in response to determining the additional topology information indicates the path is not capable of transporting network traffic between the two endpoints at the requested bandwidth at the start time for path activation, a path rejection indicating the multi-topology network is unable to satisfy the path request.