D-Link DES-3326 User Manual - Ieee 802.1Q Vlans
DES-3326 Layer 3 Fast Ethernet Switch User’s Guide
Switch Management and Operating Concepts
53
be possible on this VLAN regardless of the switch’s
operating mode.
IEEE 802.1Q VLANs
Some relevant terms:
Tagging - The act of putting 802.1Q VLAN information
into the header of a packet.
Untagging - The act of stripping 802.1Q VLAN
information out of the packet header.
Ingress port - A port on a switch where packets are
flowing into the switch and VLAN decisions must be made.
Egress port - A port on a switch where packets are
flowing out of the switch, either to another switch or to an
end station, and tagging decisions must be made.
IEEE 802.1Q (tagged) VLANs are implemented on the DES-3326
Layer 3 switch. 802.1Q VLANs require tagging, which enables
them to span the entire network (assuming all switches on the
network are IEEE 802.1Q-compliant).
VLANs allow a network to be segmented in order to reduce the size
of broadcast domains. All packets entering a VLAN will only be
forwarded to the stations (over IEEE 802.1Q enabled switches)
that are members of that VLAN, and this includes broadcast,
multicast and unicast packets from unknown sources.
VLANs can also provide a level of security to your network. IEEE
802.1Q VLANs will only deliver packets between stations that are
members of the VLAN.
Any port can be configured as either tagging or untagging. The
untagging feature of IEEE 802.1Q VLANs allow VLANs to work
with legacy switches that don’t recognize VLAN tags in packet