Does BPDU has any Ethertype or it is a Layer 2 or any explanation

[Beacon Bits]

I would like to know where BPDU (spanning-tree) sits in the network. Does it has an Ethertype that I couldn't find any? or it is Layer 2 frame of its own kind?

I have found the below image but this does not make any sense... can anyone explain in detail please?

Regards

S

[Gary Triv]

BPDU (Bridge Protocol Data Unit) is used by Spanning Tree Protocol (STP) and its variants (like RSTP) for bridge communication. BPDUs are Layer 2 frames; they don't have an IP header and, therefore, don't use an EtherType value in the same way as IP packets.

However, BPDUs do have a specific MAC destination address that helps network devices recognize and process them. The MAC destination address for STP BPDUs is 01:80:C2:00:00:00.

So, while BPDUs don't have an EtherType like IP or ARP packets, the special MAC destination address effectively serves a similar purpose: identifying the frame's content and ensuring it's processed correctly by devices that understand STP.