VLAN

[senthil_sellapillai]

In a VLAN support switch, I created a VLAN (Say VLAN id: 800) and configured four switch ports as only member port of VLAN: 800 and rest of the ports as part of default VLAN.

1. If the switch receive default VLAN traffic in VLAN 800 switch port, is the switch will forward to other default VLAN switch ports?

2. If the switch receive normal Ethernet frame without any VLAN tag in VLAN 800 switch port, will it be forwarded to default VLAN switch ports?

3. If the switch receive VLAN-800 traffic in default VLAN switch port, is the switch will forward that traffic to the VLAN 800 switch ports?

[ananddiwakar]

VLANs eseentially divide network into different broadcast domains. So two VLANs will not communicate with each other unless the traffic is routed (or L3 switched).

So if the switch receives untagged frames, i.e. in this case frames for VLAN 1, those frames will be forwarded only to the ports in VLAN 1.

Am not sure what scenario we are considering when we say that vlan 800 port receives default vlan traffic. Are we putting any port connected to another network device in VLAN 800. In this case, default vlan PCs will not be able to communicate with the remaining network.

[cisco_trouble]

Communication between VLANs i.e. Inter-VLAN communication requires a layer 3 device e.g. router or multilayer switch. Vlan800 and the native vlan should not be able to communicate without a router.

[Anand Narayana]

Hi Senthil,

Answer for all of ur 3 questions is YES, only if you have configured inter-vlan routing in the layer 3 switch. "ip routing" is the command for enabling the inter-vlan routing.

hope this helps,

rate this post.

[devang_etcom]

hi...

whenever we are talking about different VLANs then traffic of one vlan will not travel to any other VLAN... if you want to make communication between two different VLAN then you need to have layer 3 functionality...at there you may have multilayer switch or router... and you need to configure the intervlan routing on that layer 3 devices...

i think you get you your answer

rate this post if it hleps

regards

Devang