VLAN control frames

All control frames used by STP, VTP, CDP, VTP and PAgP will use VLAN 1 even if VLAN 1 is not allowed or is not configured as the native VLAN. Only DTP is the exception, which uses the configured native VLAN.

VTP revision number reset STP prio nbr value

Links:

https://forum.networklessons.com/t/introduction-to-vtp-vlan-trunking-protocol/870/196?u=lagapidis