Patent ID: 7640319
Filing Date: 2009-12-29
Classification: H04L

Abstract:
1. Virtual private network (VPN) gateway apparatus comprising a control processor to interface two or more virtual private networks (VPNs) to one or more external networks, the external network or networks having a different addressing scheme or schemes to those of the VPNs, the VPN gateway apparatus having a network address translator (NAT) shared by the VPNs, the NAT comprising a source and destination NAT, to convert VPN addresses of entities within the VPNs to addresses of the external network and to convert addresses of entities in the external network to internal addresses within an address range of a respective VPN wherein entities in the external networks appear to one of the VPNs to have an address within an address range of the respective VPN, the NAT being arranged to modify source and destination addresses for outgoing packets and pass the packets to an entity in the external network and to reconvert the modified addresses for incoming packets received in response.