convergence time MSTP , RSTP

[dhikra-marghli8]

Hello

i want to konw  what is the convergence time of each  RSTP , RVST+ and MSTP  cisco ??

i wait a reply from expert switching ?

Thanks

[DanielP211 · Accepted solution]

Hello!

The convergence time differs. PVST can take up to one minute. RSTP is around 5-10seconds. And MSTP depends on the design, but if the network is well made it can take less than 1 second.

BR

[chaitanya780]

Is there any benchmark/ reference from standard document to understand rstp convergence times 

[Joseph W. Doherty]

Benchmarks?  Doubtful.

Reference?  Well, based on the particular protocol, and what particular protocol parameters are set to, you can compute best and worst case times, but real world times are generally not best or worst case times.  Further, in real world networks, actual topology impacts convergence time along with delay on inter switch links along with each devices' processing capacity (at that time) latency.

Consider the per switch difference, hosting 100 VLANs, if only one topology needs to be computed rather than 100 topologies need to be computed.

That understood, the rapid variants are generally several seconds while the non-rapid variants may be fractional minutes.

[M02@rt37 · Accepted solution]

Hello @dhikra-marghli8 

The convergence times for different STP can vary, and it's important to note that these values can depend on the specific network conditions and configurations. However, here are general expectations for that convergence times of common STP variants (Cisco devices) :

- RSTP: Typically converges in the order of a few seconds (usually around 2-3 seconds). RSTP is designed to provide faster convergence compared to traditional STP.

- RPVST+ : Convergence Time ? Similar to RSTP, it converges in the order of a few seconds.

- MSTP: Similar to RSTP also, typically converges in a few seconds. MSTP provide flexibility and faster convergence in certain scenarios.