Vlan Configuration Examples; Using Untagged Connections - 3Com SuperStack 3 3812 Implementation Manual

VLAN
Configuration
Examples
Using Untagged
Connections
The IEEE Std 802.1Q-1998 defines how VLANs operate within an open
packet-switched network. An 802.1Q compliant packet carries additional
information that allows a Switch to determine to which VLAN the port
belongs. If a frame is carrying the additional information, it is known as
tagged.
To carry multiple VLANs across a single physical (backbone) link, each
packet must be tagged with a VLAN identifier so that the Switches can
identify which packets belong in which VLANs. To communicate between
VLANs a router must be used.
This section contains examples of VLAN configurations. It describes how
to set up your Switch to support simple untagged and tagged
connections.
The simplest VLAN operates in a small network using a single switch. In
this network there is no requirement to pass traffic for multiple VLANs
across a link. All traffic is handled by the single Switch and therefore
untagged connections can be used.
The example shown in
endstations and servers using untagged connections. Ports 1, 2 and 3 of
the Switch belong to VLAN 1, ports 16, 17 and 18 belong to VLAN 2.
VLANs 1 and 2 are completely separate and cannot communicate with
each other. This provides additional security for your network.

VLAN Configuration Examples

Figure 16 illustrates a single Switch connected to
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