switch trunk

[kcsureshbabu]

Trunk link receive without trunk tag frame what will happen the frame?

[Rasika Nayanajith]

If it is L2 switch, based on the destination MAC address of layer 2 header switch will decide where it needs to go

If it is L3 switch, it can read IP header information & decide where it should go.

HTH

Sent from Cisco Technical Support iPhone App

[Rolf Fischer]

In this case we have to differentiate control- and data frames.

Data frames will be assigned to the native VLAN, which is VLAN 1 by default, but which can be changed by configuration on a per-link basis using the switchport trunk native-vlan command.

The majority of control traffic (like CDP, VTP, IEEE STP etc.), in contrast, is processed internally in the "control plane". For this type of traffic, the native VLAN doesn't matter. There are some exceptions (like the Cisco per-VLAN SSTP BPDUs) but we want to keep it simple, right?

HTH

Rolf