Milan Technology MIL-SM2401M-STK - Manual (Page 174)

166
Tag-based VLAN (IEEE 802.1Q VLAN)
The IEEE 802.1Q specification is the standard for Port-based Tagging.
Therefore, it is possible to create a VLAN across devices from different switch
suppliers. IEEE 802.1Q VLAN uses a technique to insert a “tag” into the
Ethernet frames. The tag contains a VLAN Identifier (VID) that indicates the
VLAN numbers.
Protocol-based VLAN
In order for an end station to send packets to different VLANs, it has to be either
capable of tagging the packets it sends with VLAN tags OR be attached to a
VLAN-aware bridge. The VLAN-aware bridge must be capable of classifying
and tagging the packet with different VLAN ID. The classification and tagging
of the packets is based on default PVID and other information about the packet,
such as the protocol.
MIL-SM2401M-STK will support protocol-based VLAN classification by means
of both built-in knowledge of layer 2 packet formats used by selected popular
protocols, such as Novell IPX and AppleTalk’s EtherTalk, and some degree of
programmable protocol matching capability.