Cisco WS-C3750-48PS-S Software Configuration Manual page 286

Understanding VLANs
Figure 13-1
Figure 13-1 VLANs as Logically Defined Networks
Cisco router
Gigabit
Ethernet
VLANs are often associated with IP subnetworks. For example, all the end stations in a particular IP
subnet belong to the same VLAN. Interface VLAN membership on the switch is assigned manually on
an interface-by-interface basis. When you assign switch interfaces to VLANs by using this method, it is
known as interface-based, or static, VLAN membership.
Traffic between VLANs must be routed or fallback bridged. The switch can route traffic between
VLANs by using switch virtual interfaces (SVIs). An SVI must be explicitly configured and assigned an
IP address to route traffic between VLANs. For more information, see the
section on page 11-4
If you plan to configure many VLANs on the switch and to not enable routing, you can use the sdm
Note
prefer vlan global configuration command to set the Switch Database Management (sdm) feature to the
VLAN template, which configures system resources to support the maximum number of unicast MAC
addresses. For more information on the SDM templates, see
or refer to the sdm prefer command in the command reference for this release.
Catalyst 3750 Switch Software Configuration Guide
13-2
shows an example of VLANs segmented into logically defined networks.
Engineering
VLAN
and the "Configuring Layer 3 Interfaces" section on page
Chapter 13
Marketing Accounting
VLAN VLAN
"Switch Virtual Interfaces"
11-21.
Chapter 8, "Configuring SDM Templates,"
Configuring VLANs
Floor 3
Floor 2
Floor 1
78-16180-02