A virtual local area network switching device and an associated computer system and method are provided to permit operation in accordance with a plurality of different security classifications. The computer system includes a computer, a virtual local area network switching device and a plurality of peripheral units having different security classifications. The virtual local area network switching device may include a computing device that includes the plurality of ports and that is configured to control communications with the peripheral units in accordance with the respective security classifications. The virtual local area network switching device may also include a memory device configured to store information associating the plurality of the ports with the security classification of the respective peripheral unit. The memory device may also store information associating each port with both a logical address and a physical address of the respective peripheral units.