lagapidis
November 5, 2020, 8:43am
75
Hello Eyad
The generation of TCNs is different for standard STP and for RSTP. This lesson describes the procedure for standard STP. The following post describes the TCN for RSTP.
Hello Michael
Convergence is the state that a topology of switches achieves as a result of going through the STP processes and mechanisms to reach a stable spanning-tree topology. Convergence takes place both at the time of the initial connection of the network, as well as when the topology changes. Any event that causes a change in topology, will inevitably also cause STP to attempt to achieve convergence once again. So both situations that you describe are considered convergence.
There …
Yes, you are correct, ports that are enabled with portfast will not generate TCNs for either STP or RSTP.
Eyad:
Is the BPDU will be only generated by the root-switch, while the non-root-switch will just forward the received BDPD in the old spanning tree (IEEE 802.1d)?
Is the BPDU will be generated by the root-switch as well as non-root-switch new spanning tree (rapid STP) (IEEE 802.1w)?
For both of these questions, take a look at the following post:
Hello Jesus
When plain STP is implemented (that is, 802.1D) then yes, only the root bridge generates BPDUs and they are relayed by the rest of the switches that receive them. However, in RSTP, all switches generate BPDUs. This is further described in the following Cisco documentation:
I hope this has been helpful!
Laz
I hope this has been helpful!
Laz