spanning tree convergence

jcarrillo26

i was wondering i know that 802.1d has a convergence time of 50 seconds. what is the convergence time of 802.1w, i think i read somewhere that it is like 15 seconds, am i wrong?

late_collision

It depends. Best case scenario, as fast as the switches can exchange and agree on proposal-agreement handshakes. Worst case, as fast as 802.1D.

RSTP uses a series of proposals to determine a loop free topology. It is not timer based, convergence can happen as fast as BPDU's can be exchanged. RSTP can detect a loss of BPDU's in a time period of 3x Hello Interval (which is 2 seconds by default), so a max of 6 seconds. This is similar to 802.1D's Max Age timer. However, if the switches are connected to a shared media or to switches running 802.1D, convergence will happen at 802.1D speeds for those links.

jcarrillo26

hey thanks for your feedback i appreciate it.