Patent ID: 7028337
Filing Date: 2006-04-11
Classification: H04L

Abstract:
1. A Virtual Private Network (VPN) communication method employed for a security gateway apparatus connecting between a local area network (LAN) and a wide area network (WAN) including a public network, the communication method comprising the steps of: a) assigning a first IP address to a terminal outside said LAN; b) adding a Dynamic Host Configuration Protocol (DHCP) communication option to an Internet Key Exchange (IKE) data, when establishing an IKE communication with said terminal outside the LAN having a connection with the WAN; c) assigning a second IP address from an inside terminal within the LAN to the terminal outside the LAN during the IKE communication, said second address regardless of said first address; and d) establishing a Security Architecture for the Internet Protocol (IPsec) communication that follows the IKE communication, which includes said first IP address and said second IP address, wherein the gateway apparatus designates the first IP address for the outside terminal from a tunneled IP packet.