[c-nsp] stp on me3600 on efp's with locally connected older switch

[Christian Meutes]

> And if anyone has any suggestions about designing loop prevention via
> me3600's when I'm connecting legacy vlans over vpls via my mpls cloud then
> fire away.

There isn't much you can do afaik: STP on ACs (CE-only, and consistent port configurations / prone PVSTP), waiting for MST-AG or even MC LAG, keep away from loop-capable ACs per L2 site.