Extreme Networks ExtremeWare 7.2e, Installation And User Manual

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Types of VLANs
ExtremeWare 7.2e Installation and User Guide 95
Assigning a VLAN Tag
Each VLAN may be assigned an 802.1Q VLAN tag. As ports are added to a VLAN with an 802.1Q tag
defined, you decide whether each port will use tagging for that VLAN. The default mode of the switch
is to have all ports assigned to the VLAN named default with an 802.1Q VLAN tag (VLANid) of 1
assigned.
Not all ports in the VLAN must be tagged. As traffic from a port is forwarded out of the switch, the
switch determines (in real time) if each destination port should use tagged or untagged packet formats
for that VLAN. The switch adds and strips tags, as required, by the port configuration for that VLAN.
NOTE
Packets arriving tagged with a VLANid that is not configured on a port will be discarded.
Figure 16 illustrates the physical view of a network that uses tagged and untagged traffic.
Figure 16: Physical diagram of tagged and untagged traffic
Figure 17 is a logical diagram of the same network.
ES4K008
1 2 3 4 A B 5 6 7 8
4
3
2
1
System 1
= Marketing
= Sales
M
M
S
S
M
S
S
S
= Tagged port
Marketing & Sales
M
M
S
S
System 2
M S M S
S S
802.1Q
Tagged server
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