Chapter 10 Configuring Vlan - Cisco WS-C2950SX-48-SI Configuration Manual

Understanding How VLANs Work
Figure 10-1 VLANs as Logically Defined Networks
Cisco router
Ethernet
VLANs are often associated with IP subnetworks. For example, all the end stations in a particular IP
subnet belong to the same VLAN. Traffic between VLANs must be routed. Port VLAN membership on
the switch is assigned manually on a port-by-port basis. When you assign switch ports to VLANs using
this method, it is known as port-based, or static, VLAN membership.
The in-band (sc0) interface of a switch can be assigned to any VLAN, so that you can access another
switch on the same VLAN directly without a router. Only one IP address at a time can be assigned to the
in-band interface. If you change the IP address and assign the interface to a different VLAN, the previous
IP address and VLAN assignment are overwritten.
You can set the following parameters when you create a VLAN in the management domain:
• VLAN number
• VLAN name
VLAN type (Ethernet)
•
VLAN state (active or suspended)
•
Maximum transmission unit (MTU) for the VLAN
•
Security association identifier (SAID)
•
VLAN number to use when translating from one VLAN type to another
•
Note When translating from one VLAN type to another, you must create a different VLAN number for each
media type.
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide
10-2
Catalyst 4000
Catalyst 4000
Fast
Catalyst 4000
Engineering Marketing
VLAN VLAN
Chapter 10 Configuring VLANs
Accounting
VLAN
Floor 3
Floor 2
Floor 1
—
Release 8.1
78-15486-01