Abstract: Apparatus for transferring data, including a first gateway, adapted to operate as a first switch in a first storage area network (SAN) operating according to a Fiber Channel protocol, and which is coupled to receive a data-frame addressed to a virtual address of a receiving client operative in a second SAN. The apparatus also includes a second gateway, adapted to operate as a second switch in the second SAN, which operates according to the Fiber Channel protocol substantially independently of the first SAN. The second gateway is coupled to receive the data-frame from the first gateway, and is adapted to look up a local address of the receiving client in the second SAN by using at least part of the virtual address as an index to an incoming-data-frame translation table, and to transmit the data-frame addressed to a local address of the receiving client.