Methods and systems for selectively processing virtual local area network (VLAN) traffic from different networks while allowing flexible VLAN identifier assignment

Methods and systems for selectively processing VLAN traffic from different networks while allowing flexible VLAN identifier assignment are disclosed. According to one aspect, a layer 2 switch includes a virtual switch identifier data structure that associates a VLAN identifier extracted from a layer 2 frame and a port identifier corresponding to a port on which a frame is received with a virtual switch identifier. The virtual switch identifier is used to select a per-virtual-switch data structure, such as a forwarding table. The per-virtual-switch data structure is used to control processing of the layer 2 frame on a per-virtual-switch basis. The per-virtual-switch data structure may also be updated separately from the data structures assigned to other virtual switches.