If Port P0 gets the deal, Port P0 can immediately switch to transmission. Port P3, which was in a state of rejection after synchronization, is in exactly the same condition as Port P0 before receiving the agreement. Port P0 then begins to propose to its neighbor and tries to move quickly to the transmission. This handshake mechanism spreads rapidly to the edge of the network and quickly restores connectivity after a change in topology. The SWB will restore all of its ports and send its own BPDU proposal to its neighbours downstream, if it receives a response from its neighbours downstream, it will redirect its base port and send a BPDU agreement to SWA, set at 1, and the notice of the proposal will be set at 0. SWA ports will switch to redirection. 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. Switch A reacts to the root switch with a transmission agreement.

Both Switch ports move quickly to the redirect state with the certainty that there will be no layer 2 loops. For the next downstream switch, the upper BPDU is transferred to the designated and recurrent states of its non-rejectionants, completing the proposal/agreement process. Ранее, для того, чтобы убедиться, что порт может участвовать в передаче данных, требовались таймеры, т.е. свич пассивно ждал в течение означенного времени, слушая BPDU. RSTP – RSTP – Full Duplex – Full Duplex (-. .