Patent ID: 8805977

Claim:
A method for resolving conflict between addresses assigned in an internet protocol (IP) remote access system between a client and an internal network via a server connected to the client via an external communication network, the client being arranged behind a network address translation (NAT) router, the method, carried out by the server, comprising: receiving a request from the client for a virtual IP address to communicate with the internal networks of the server along with IP address information of the client for conflict resolution; comparing the IP address information of the client with a plurality of internal network addresses of the internal networks of the server for any conflicts of addresses to determine conflicted internal network subnet addresses; assigning a conflict resolving network subnet address for each conflicted internal network subnet address conflicting with the IP address information of the client; mapping each conflicted internal network subnet address of the internal network of the server to the assigned conflict resolving network subnet address for the client; and sending a reply with the assigned conflict resolving network subnet addresses and non conflicting virtual IP address to the client for enabling communication between the client and the internal network via the server, wherein the client is an internet protocol security remote access client (IRAC) and the server is an internet protocol security remote access server (IRAS), and the client and server use internet key exchange version 2 (IKEv2) for IP security (IPSec) tunnel establishment.