CIsco 831 vlans

[alucky8ball]

Hi,
Does anyone know if a Cisco 831 router can route vlans over the 4 port switch on the unit, or can it only support 4 devices coming out of the ports on the switch? If you can vlan the ports on the back of the router (E0) then could you please tell me how to do it.

 

[ADB100]

As far as I know there is no support for VLAN's on the 831. With newer IOS releases the 831, 836 & 837 have the ability to enable 2 separate Ethernet interfaces on the 4-port switch - i.e. you had Ethernet 1 and Ethernet 2. This allowed you to create a DMZ type setup.

New Features
DMZ-Demilitarized Zone
Cisco 831, Cisco 836, and Cisco 837-All feature sets.

DMZ provides an additional Ethernet interface, Ethernet 2, that, when enabled, has the Fast Ethernet 4 port on the LAN side switch as its physical representation. This interface acts as an additional LAN or WAN side interface on Layers 2 and 3 and allows for an additional DMZ leg that can be used for several different purposes. For example, this may include a separate LAN network where traffic to and from the other interfaces can be controlled by access control lists. The behavior of the Cisco IOS firewall is the same as other Ethernet Interfaces. Any state of the switch port is reflected on the Ethernet 2 port once it is put in a "no shut" state.

Because of architectural constraints, performance between Ethernet 0 and Ethernet 2 interfaces and performance to each of these ports from the WAN interface may not be at full Ethernet speeds. The impact will vary, depending on the load on the other interface (Ethernet 0 versus Ethernet 2). In most cases this limitation is not noticeable because the WAN speeds are usually fractions of 10 Mbps.

http://www.cisco.com/en/US/partner/products/hw/routers/ps380/prod_bulletin0900aecd800f8567.html

HTH

Andy