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TRILL: The end of Spanning-Tree?

Published on March 9, 2011 By Jose Miguel Huertas

For all of those who fear spanning-tree, I’m sure the tittle got your attention, at least for a while. For those who support SPT, I must say don’t panic,  the end of SPT is not so close. All of us know we need spanning-tree in a Layer 2 network, even more when there are built-in [...]

BPDUGuard vs BPDUFilter

Published on January 17, 2011 By Jose Leitao

Two security features for Spanning-tree BPDUs with similar names but very different results. Background To exchange information between bridges, Spanning-Tree uses a special data frame called Bridge Protocol Data Unit (BPDU), with the information Spanning-Tree can build a stable loop-free topology. If you have a rogue device – the classic example being those little 8 [...]