Patent ID: 8725883

Claim:
A method comprising: obtaining a first address from a first network to a network protocol entity within a mobile node, said first address comprising an internet protocol address and a port number, wherein the first address is a private address of the mobile node within the first network; receiving network address translation information regarding network address translation between the first network and a second network from a first network node to a session proxy entity within said mobile node; configuring an address mapping between said first address and a second address to said first network node from said session proxy entity, said second address being a public address comprising an internet protocol address and a port number; processing a session establishment request at said session proxy entity in said mobile node, said request comprising at least one first field comprising said first address and at least one second field comprising a third address, said third address comprising an internet protocol address and a port number; replacing said first address with said public second address in said at least one first field by said session proxy entity; configuring an address mapping between said third address and a fourth address to said first network node from said session proxy entity, said fourth address being a public address comprising an internet protocol address and a port number; and initiating a sending of said session establishment request to a remote network node from said session proxy entity within said mobile node.