
IES-1248-51V User’s Guide
409
CHAPTER 56
IEEE 802.1Q Tagged VLAN and
Isolation Commands
This chapter describes the IEEE 802.1Q Tagged VLAN commands as well as
command used to configure the isolation feature on the IES-1248-51V.
56.1 IEEE 802.1Q Tagging Types
There are two kinds of tagging:
• Explicit Tagging
A VLAN identifier is added to the frame header that identifies the source VLAN.
• 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 IES-1248-51V 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).
56.2 Filtering Databases
A filtering database stores and organizes VLAN registration information useful for
switching frames to and from the IES-1248-51V. A filtering database consists of
static entries (Static VLAN or SVLAN table).
Kommentare zu diesen Handbüchern