1. A method of implementing storage virtualization on a network device of a storage area network, the method comprising: (a) receiving a frame or packet at a port of the network device; (b) determining that the frame or packet pertains to access of a virtual storage location of a virtual storage unit representing one or more physical storage locations on one or more physical storage units of the storage area network; (c) obtaining a virtual-physical mapping between the one or more physical storage locations and the virtual storage location; and (d) sending a new or modified frame or packet to an initiator or a target specified by the virtual-physical mapping.