1. For use in a first device and a second device of a transport network adapted to provide a transparent LAN segment service, a method for processing ingress data received by a port of the first device, the method comprising: a) at the first device, determining a layer 2 destination address associated with the ingress data; b) at the first device, attempting to determine a first label using the layer 2 destination address; and c) if the first label is determined, then i) at the first device, adding the first label to at least a portion of the ingress data to generate modified data; ii) at the first device, identifying, based on the port on which the data was received, a transparent LAN segment with which the ingress data is associated; iii) at the first device, forwarding the ingress to a second device that the first device associates with the transparent LAN segment; iv) at the second device, using the first label to determine a second label and tunnel information; v) at the second device, adding the second label to at least a portion of the modified data to generate twice modified data; and vi) forwarding the twice modified data towards a third device based on the tunnel information.