To be a CCIE we need a good grasp of switching and STP. This post by Petr Lapukhov (again) is one of the best I’ve ever seen on STP. This post describes PVST+ in detail. Read it here.
I’ve added some more flashcards. The latest addition contains some questions on QoS, EEK, BGP and OSPF authentication etc. The total number of flashcards now exceeds 260. Download as usual from here.