[c-nsp] Best Practices for Transporting Layer-2 Services

[Shawn L]

I'm wondering what other providers are doing when they need to transport a
bunch of third-party layer-2 services?

For Example -- if another SP wants to hand you 3 vlans (for example
10,11,12) and have you transport them to a couple of sites.  Vlan 10 (could
be Q-in-Q or not) needs to go to sites A and B, vlan 11 (again could be
Q-in-Q) needs to go to sites C and D, etc.

I'm specifically asking (in a cisco world) what do you do to protect
yourself from any funny business (spanning tree, whatever) that may happen
on the other provider's network or on the end-customer's network.

Thanks

Shawn