Chapter 7: Virtual LANs
76 Section I: Using the Menus Interface
Each port must be assigned a PVID. This value must match the
VLAN’s VID and it must be the same for all the ports in a port-based
VLAN. You must manually configure this value on a port after you
assign the port to a VLAN. For instructions, refer to “Configuring the
PVID of Untagged Ports” on page 87.
A port-based VLAN that spans multiple switches requires a port on
each switch where the VLAN is located to function as an
interconnection between the switches where the various parts of the
VLAN reside.
If there are end nodes in different VLANs that need to communicate
with each other, a router or Layer 3 switch is required to interconnect
the VLANs.
The switch can support up to a total of 256 port-based and tagged
VLANs.
Drawbacks of
Port-based
VLANs
There are several drawbacks to port-based VLANs:
It is not easy to share network resources, such as servers and printers,
across multiple VLANs. A router or Layer 3 switch must be added to
the network to provide a means for interconnecting the port-based
VLANs. The introduction of a router into your network could create
security issues from unauthorized access to your network.
A VLAN that spans several switches requires a port on each switch for
the interconnection of the various parts of the VLAN. For example, a
VLAN that spans three switches would require one port on each switch
to interconnect the various sections of the VLAN. In network
configurations where there are many individual VLANs that span
switches, many ports could end up being used ineffectively just to
interconnect the various VLANs.