Native VLAN

jason_lunde

Real quick question....for security reasons I do not want any untagged traffic passing over trunk lines within a certain part of my network. The question is...if I do not add the native vlan to my switchport trunk allowed vlan list...will it block the sending of untagged traffic over the trunk? Thanks...this should be a no-brainer...but I just wanted to <hopefully> confirm what I already was thinking.

Thanks guys!

networker050184

Yes, if you prune the native VLAN off the trunk then no untagged traffic will be sent. You can also use the vlan dot1q tag native command which will cause the switch to tag traffic on the native vlan and drop untagged frames on trunk links.

jason_lunde

much obliged!