Will this work if one end is set to QinQ, and the other end is set to an access port?  Will this strip the QinQ tagging, or will we be able to decapsulate the inner Vlan's later on in our network?

Not sure why you'd want to use an access port, since the whole point of QinQ is to be able to preserve all your VLAN tags through the provider cloud.

I don't know if trunk port is a requirement, but in theory the PE would just append a metro tag on packets coming out of your access port.

In the provider cloud, packets would only have one tag instead of two.

You should be able to lab this out w/ four 3560's.

^^Thanks

As I understand it, a dot1q-tunnel is configured at one end, and a dot1q trunk to break the Vlan's configured out on the other.

For commercial reasons we are using a 'transit provider' to provide backhaul between the service provider and ourselves.  I suspect the transit provider can't break the VLAN's out with a dot1q trunk as they would likely conflict other Vlan's in their transit network.

As is currently setup a cisco compatible QinQ tunnel is set at the service provider edge, and is matched with a QinQ tunnel on what I believe is a Cisco switch on the transit provider edge.  I wasn't sure if this setup was compatible, which would appear to add yet another layer of tagging, hence my previous question on configuring the transit provider edge as an access port.

I'll try and lab it out, but if anyone could further comment on this it would be really appeciated.