Patent ID: 7908651
Filing Date: 2011-03-15
Classification: H04L

Abstract:
1. A method of network communication between a secure network and remote clients by way of an intermediate transport network, wherein the secure network is connected to the intermediate transport network through a security gateway and a NAT-T (Network Address Translation-Traversal) proxy is between the security gateway and the intermediate transport network, wherein a secure communication session is a NAT-T IKE (Internet Key Exchange protocol) session in which the type of session negotiated by NAT-T IKE between the secure network and remote clients is IPsec (IP Security), and in which initiator and responder cookies in an ISAKMP (Internet Security Association and Key Management Protocol) header of a packet are used to identify a packet as part of an established session, wherein the remote clients share a common source address on the intermediate transport network; and wherein in the NAT-T proxy, the method comprises: a) analyzing packets received from a remote client to identify those packets that represent the start of a new secure communication session; b) assigning a session-unique IP address to the new secure communication session to be established by the identified packet; c) translating all packets in the secure communication session by exchanging their source address with the local session-unique IP address; and d) routing the translated packets to the security gateway whereby packets received by the security gateway have, for each established session, a unique IP address.