Patent ID: 8295285
Filing Date: 2012-10-23
Classification: H04L

Abstract:
1. A method of communicating data packets between a first communications device in a first local network and a second communications device in a second local network, wherein private IP addresses are used for devices in the first and second local networks, comprising: establishing a VPN (Virtual Private Network) tunnel between a first gateway serving the first local network and a second gateway serving the second local network, wherein a public IP address has been assigned to each gateway; defining, in the first gateway, a selected internal IP address space to be used in the first local network for devices in the second local network, the selected internal IP address space being separate from an internal IP address space used in the first local network for devices in the first local network; receiving, in the first gateway, an incoming data packet from the second device via said VPN tunnel, the incoming packet having an internal IP header including a first internal destination address used in the second local network for the first device and a first internal source address used in the second local network for the second device; changing the first internal destination address to a second internal destination address used in the first local network for the first device; changing the first internal source address to a second internal source address that is within the selected internal IP address space and is used in the first local network for the second device; and forwarding the incoming packet to the first device with a modified internal IP header including the changed second internal destination address and the changed second internal source address.