HP ProCurve Switch 6120G/XG Management Manual page 34

Red Server
Red
VLAN
Red
VLAN
Figure 2-4. Example of Connecting Multiple VLANs Through the Same Link
Introducing Tagged VLAN Technology into Networks Running Legacy
(Untagged) VLANs. You can introduce 802.1Q-compliant devices into net-
works that have built untagged VLANs based on earlier VLAN technology. The
fundamental rule is that legacy/untagged VLANs require a separate link for
each VLAN, while 802.1Q, or tagged VLANs can combine several VLANs in one
link. This means that on the 802.1Q-compliant device, separate ports (config-
ured as untagged) must be used to connect separate VLANs to non-802.1Q
devices.
The legacy (non-802.1Q
compliant) switch requires a
separate link for each VLAN.
Red
VLAN
Non-802.1Q
Switch
Blue
VLAN
Figure 2-5. Example of Tagged and Untagged VLAN Technology in the Same
Network
For more information on VLANs, refer to:
■ "Overview of Using VLANs" (page 2-45)
■ "Menu: Configuring VLAN Parameters (page 2-21)
Blue Server
ProCurve
Switch
Blue
VLAN
Red Server
Blue Server
Red VLAN
ProCurve
Switch
Blue VLAN
Blue
VLAN
Red
VLAN
Static Virtual LANs (VLANs)
Static VLAN Operation
The same link carries Red
VLAN and Blue VLAN traffic.
Red
ProCurve
VLAN
Switch
Blue
VLAN
VLAN tagging
enables the Link to
carry Red VLAN and
Blue VLAN Traffic
ProCurve
Switch
Blue
VLAN
Red
VLAN
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