Automatic VLAN ID discovery for ethernet ports

A method, system and network protocol that enables each host within a virtual local area network (VLAN) environment to automatically discover to which VLANs the host belongs. When a host initially sets up a communication interface, the host generates a series of probing packets, each including a different one of the range of possible VLAN IDs within the packet header. The probing packet requests a response from the switch indicating whether the corresponding VLAN (identified by the VLAN ID) is supported by the switch. The switch automatically drops any packets with a VLAN ID not recognized/supported/configured in the switch. The destination device only receives supported packets, and thus the interface only receives a response for those request packets having a VLAN ID associated with a supported VLAN. The host's interface then knows which VLAN ID(s) are supported, and the host assigns/utilizes only those VLAN IDs for outgoing traffic.