Patent ID: 8780721
Filing Date: 2014-07-15
Classification: H04L

Abstract:
1. A network control method using a controller that controls flows of a plurality of nodes, the method comprising: in shifting a flow that passes through a specific node onto an alternative path which does not pass through the specific node passed through by the flow, the controller finding a plurality of alternative candidate paths, each which has a same source and a same destination as a path associated with the flow to be shifted, and does not pass through the specific node passed through by the flow to be shifted; the controller determining the alternative path from the plurality of alternative candidate paths according to a predetermined criterion; the controller aggregating a plurality of flows of a node on the alternative path, the flow passing through the specific node being shifted thereto, the node, on reception of a packet, matching a header of the packet with a rule of a flow entity in the node to perform an operation based on an action of the flow entity that defines an operation for the received packet matching with the rule, the flow entity in the node being set by the controller, wherein the controller holds in an aggregated path storage unit an aggregated path management table comprising at least an entry, associated with a node with flows thereof aggregated, the entry including: a node identifier to identify the node; and a pointer to an aggregated flow entity table, the aggregated flow entity table including: an aggregated flow entity including a rule and an action for the aggregated flow; and a list of pointers to respective flow entities that are aggregated, the controller, in performing flow aggregation, updating the aggregated flow entity table pointed by the pointer associated with the node with flows thereof aggregated, in the aggregated path management table; and the controller updating with the aggregated flow entity the flow entity in the node.