STP is a really great feature as you know and after examining PVST, it is time to take a look to RSTP ! The first letter “R” , refers to Rapid ! As you can understand from it’s name, rapid spanning tree is faster than STP. Rapid means that this protocol converges faster. And protocol’s name is 802.1W.
As you know, port modes of STP is listening, learning, blocking / forwarding. It’s a little bit different in RSTP. RSTP port modes are ;
–Discarding
–Learning
–Forwarding
And as you know again port roles of STP is root, designated and blocked. It’s a little bit different in RSTP. RSTP port states are ;
–Root port
–Designated
–Alternate (Trick : STP forgets the blocked port and never uses it again. But if you are using RSTP switch reminds the alternate port and keeps it ready for redundancy)
And finally, I want to show you how you can activate the RSTP ( Nowodays it is mostly open defaultly )
SWITCH_A(conf)#spanning-tree mode rapid-pvst (Same config for Switch B and C)