PVST protocol frames
As shown in Figure 27, a PVST BPDU uses the same format as an RSTP BPDU except the following differences:
The destination MAC address of a PVST BPDU is 01-00-0c-cc-cc-cd, which is a private MAC address.
Each PVST BPDU carries a VLAN tag. The VLAN tag identifies the VLAN to which the PVST BPDU belongs.
The organization code and PID fields are added to the LLC header of the PVST BPDU.
Figure 27: PVST BPDU format
A port's link type determines the type of BPDUs the port sends.
An access port sends RSTP BPDUs.
A trunk or hybrid port sends RSTP BPDUs in the default VLAN and sends PVST BPDUs in other VLANs.