A gateway device including an access interface to an external network, a trunked interface, and translation logic. The access interface is associated with multiple external source addresses. The trunked interface is interfaced with multiple different virtual local area networks (VLANs), where each VLAN is associated with a corresponding VLAN tag and at least one of potentially overlapping internal source addresses. The translation logic translates between each external source address and each unique combination of internal source address and VLAN tag. A method of network address translation including assigning one of first network addresses to each first device of a first network, dividing the first network into a plurality of VLANs, separating the first devices with the same first network address into different VLANs, and assigning first devices with the same first address to different second network addresses.