Patent ID: 8576845
Filing Date: 2013-11-05
Classification: H04L

Abstract:
1. A method of controlling transmission of data packets in a packet-switched network, comprising the following steps performed by a router in the network: receiving a data packet comprising an ingress tag derived from a sender key or router key using a first tag derivation function TDF known by the router, wherein the sender key or the router key have been encoded by the first TDF to conceal the sender key or the router key from a third party that does not know the first TDF; executing a matching operation to the received ingress tag and at least one entry in a forwarding table, said entry comprising an ingress key and a corresponding outgoing port number, using said first TDF to decode the ingress key in the said entry in the forwarding table to determine whether the received ingress tag matches the decoded ingress key in said entry; and in response to finding a matching entry in the forwarding table, sending the packet to a next hop node from an outgoing port indicated in the matching entry in the forwarding table, and responding to not finding a matching entry in the forwarding table by discarding the packet.