The explanation is great. I have only one doubt, will the root bridge be chosen before the procedure of seizing the hand of the proposal/agreement? If so, why is the BPDU proposal called a superior BPDU? Every 2 seconds, she tries to send a proposal, but does not get an agreement. After 15 seconds, the timer stops and the RSTP must go through the regular phases instead of putting the port online immediately. When a new connection is created between root and Switch 1, both ports are moved to a certain blocking state until they receive a BPDU of their equivalent. The proposal bit on BPDUs is only fixed and sent if a designated port is in a state of rejection or learning. This process occurs for port P0 of the main deck. As Switch 1 receives superior information, Switch 1 immediately knows that Port P1 is the new root port. Switch 1 then ensures that all ports are synchronized with this new information. Yes, the debugging process does not indicate this, but it is synchronized after receiving the agreement. If an alternative P2 port, a specific P3 redirect port and an Edgeport P4 are present on Switch 1, P2 and P4 already meet one of the criteria. To be synchronized, Switch 1 must block the P3 port and give it the pier`s attribution status. When all ports are synced, Switch 1 can remove the blocking from the newly selected P1 port and respond to the strain by sending a message of agreement.
This post is a copy of the BPDU proposal with the bit of agreement instead of the proposal bit. This copy ensures that Port P0 knows exactly which proposal corresponds to the agreement to which it corresponds. The BPDU is a proposal and the expected bit is fixed. He is not yet trying to learn or advance on the port. SW2 starts all ports as planned and starts sending suggestions. It then gets a better BPDU from SW1, so it has to synchronize its ports downstream (Et0/1). Let`s take a look at the mechanics of the RSTP`s operation. To follow this a little more simply, let`s start with an analogy. Imagine (R) STP as a traffic light control mechanism in a city.
Sometimes it may be necessary for the city`s transportation department to divert traffic from one street to another to reduce traffic congestion. But what if the controller of one crossing is not connected to the controller at another intersection? – After the reciprocal exchange of BPDUs, which ultimately contain suggestions, each switch will be aware that the connection must remain blocked, because the base port on both switches will not be changed. Therefore, after replacing the BPDUs on the S2-S3 connection, it will be immediately clear which port is the designated port and what is the alternative port on that connection. The alternative port no longer sends BPDUs and remains in a state of rejection, while the designated port slowly moves from rejection to “Learn” to redirect state. However, no agreement is sent from the two switches and no other non-edge port is blocked due to the receipt of a proposal. In the event that the proposal and the agreement process fail RSTP must rely on the old cars used in the regular stPs. There is a timer called FdWhile, which is identical to the forward deceleration and is 15s by default. After trying to send proposals for 15zus, he will begin to bring the port by releases, learning, and then for transmission.