802.1Q and Native Vlan

akhran1974 · ‎04-20-2008

Under normal circumstances, when a untagged frame reaches the end of the trunk link, the frame will be assumed to belong to the native vlan of the trunk link. The 802.1Q tag will be removed and the frame will be forwarded out to those ports in the native vlan.

If a trunk port receives a 802.1Q frame that is tagged with the native vlan tag, what happens to the frame?

Thanks.

Jon Marshall · ‎04-20-2008

The native vlan does not have an 802.1Q tag associated with it ie. it is untagged. So a trunk port won't receive a frame in the native vlan with a tag on it because by definition the native vlan doesn't have a tag.

Jon

jcoke · ‎04-20-2008

The frame is dropped.

bvsnarayana03 · ‎04-20-2008

frames from native vlans are always untagged.so there's no chance of recvng a frame with tag.