I'm comparing network emulation in FreeBSD against performance of an actual in-service network. The network uses rapid spanning tree protocol to reconfigure if a link fails. Testing with the actual network shows around 20 milliseconds of down time before the route is adjusted after link failure. This is tested with a ping utility. Best times for the emulated network are around 600 milliseconds. I don't expect the emulated network to be exactly the same, but would have expected it to be closer than this. I have been unable to find much information about the FreeBSD RSTP implementation. Can anyone point me in the right direction or shed some light on this?