[c-nsp] BPDU age timer in Metro E networks

Jim McBurnett jim at tgasolutions.com
Mon Sep 29 00:16:02 EDT 2008


Hello folks,
I am looking at a strange issue and I was wondering how some of you have seen this done..
On a Metro E connected network with 5+ links and in some cases several fiber interconnect switches between the sites.

Typically, on a LAN every time a BPDU crosses a switch the MAX AGE time is reduced by 1 every time it crosses a switch.
So that makes me ask, do Metro E switches do this? I suspect yes, unless some kind of QinQ parameter change in effect.
Fiber management devices?IE fujikura, or ??


In this case the layer 2 spanning tree topology, if extended via Metro E, the Metro Layer 2 hops count towards the diameter of the spanning tree topology?
How does QinQ tunneling impact this if at all?

Thanks,
Jim




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