SMC Networks SMC6624M Management Manual page 238

Configuring Advanced Features
Port-Based Virtual LANs (Static VLANs)
saved by not allowing packets to flood out all ports. An external router is
required to enable separate VLANs on a switch to communicate with each
other.
For example, referring to figure 9-39, if ports 1 through 4 belong to VLAN_1
and ports 5 through 8 belong to VLAN_2, traffic from end-node stations on
ports 2 through 4 is restricted to only VLAN_1, while traffic from ports 5
through 7 is restricted to only VLAN_2. For nodes on VLAN_1 to communicate
with VLAN_2, their traffic must go through an external router via ports 1 and 8.
Figure 9-39. Example of Routing Between VLANs via an External Router
Overlapping (Tagged) VLANs. A port on the SMC6624M switch can be a
member of more than one VLAN if the device to which it is connected complies
with the 802.1Q VLAN standard. For example, a port connected to a central
server using a network interface card (NIC) that complies with the 802.1Q
standard can be a member of multiple VLANs, allowing members of multiple
VLANs to use the server. Although these VLANs cannot communicate with
each other through the server, they can all access the server over the same
connection from the switch. Where VLANs overlap in this way, VLAN "tags"
are used to distinguish between traffic from different VLANs.
9-48
External
Router
Switch with Two
VLANs Configured
Port 2
VLAN_1
Port 3
Port 4
Port 1
Port 5
Port 8
Port 6
Port 7
VLAN_2