ZyXEL Communications ZyXEL Dimension ES-3024 - Manual (Page 147)

Dimension ES-3024 Ethernet Switch
IEEE 802.1Q Tagged VLAN 23-1
Chapter 23
IEEE 802.1Q Tagged VLAN
This chapter describes the IEEE 802.1Q Tagged VLAN and associated commands. Use the “config
save” command to save configuration changes.
23.1 IEEE 802.1Q Tagged VLAN Overview
See the VLAN Setup chapter for more information on VLANs. There are two kinds of tagging:
1. Explicit Tagging
A VLAN identifier is added to the frame header that identifies the source VLAN.
2. Implicit Tagging
The MAC (Media Access Control) number, the port or other information is used to identify the source of a VLAN
frame.
The IEEE 802.1Q Tagged VLAN uses both explicit and implicit tagging.
It is important for the switch to determine what devices are VLAN-aware and VLAN-unaware so that it can decide
whether to forward a tagged frame (to a VLAN-aware device) or first strip the tag from a frame and then forward it
(to a VLAN-unaware device).
23.2 Filtering Databases
A filtering database stores and organizes VLAN registration information useful for switching frames to and from a
switch. A filtering database consists of a static entries (Static VLAN or SVLAN table) and dynamic entries
(Dynamic VLAN or DVLAN table).
23.2.1 Static Entries (SVLAN Table)
Static entry registration information is added, modified and removed by administrators only.
23.2.2 Dynamic Entries (DVLAN Table)
Dynamic entries are learned by the switch and cannot be created or updated by administrators. The switch learns
this information by observing what port, source address and VLAN ID (or VID) is associated with a frame. Entries
are added and deleted using GARP VLAN Registration Protocol (GVRP), where GARP is the Generic Attribute
Registration Protocol.
23.3 Configuring Tagged VLAN