The order of the steps is not quite correct. Yes, he should follow this order: very good explanation on rstp. I have my doubts. if the choice of root bridge (proposal and agreement) is made in parallel between each switch, as you explained in order, how do they make the same passage between sw1 – sw2 and sw3-sw4? On the connection between S4 and S2, the F0/2 of the S4 is the designated port, while the Fa0/2 of the S2 is the root port, so the S2 should not send suggestions for this link. The right sequence of events is therefore that the S4 sends a proposal to the S2 and responds with an agreement on S4 after blocking all its non-edge ports. I explained it one after another, because it would be very chaotic to explain PoV of all the switches at once. If a designated rejection port does not get an agreement after sending a proposal, it slowly switches to the transmission state and refers to the traditional 802.1D listening sequence. This can happen if the remote RSTP-BPDUs bridge does not include or if the remote bridge port is blocked. (To emphasize a very important fact before going in order of steps, remember that the port of the SWA appears as designated discarding, as it is the default port role and the default status in RSTP.
Each designated discarding (and Designated Learning Learning) port sends BPDUs with the entire bit proposal. The SWB port will also appear as a designated discard and can also send suggestions, but it is not relevant at this stage, because after receiving a superior BPDU, the port role of SWB changes from SWA to root.) This is the best blog I`ve studied. Thank you very much! If a new point-to-point connection is added between two switches, both ports will appear as designated discarding, the default role. Ports in a state of discarding or learning send BPDUs with the entire bit proposal, both switches do so provided they have the right to be designated. SWA sends its superior BPDU to SWB, whose port begins in the launcher. SWB concludes that you have made RSTP communication simple and clear. Thank you for your very detailed explanation. I`ll use the topology below to go through the synchronization process. In RSTP, only non-edge ports moved to redirect status cause a change in topology.