HP ProCurve series 2500 Management And Configuration Manual page 246

Configuring Advanced Features
Port-Based Virtual LANs (Static VLANs)
Figure 9-40. Example of Overlapping VLANs Using the Same Server
Similarly, using 802.1Q-compliant switches, you can connect multiple VLANs
through a single switch-to-switch link.
Figure 9-41. 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.
9-52
Switch 2512 or 2524
Switch Switch
2512 2524
Switch
2512