Same C-TAG to Multiple S-TAG - QinQ Mapping

[Oleksandr Y.]

Hello Community, got another riddle for you ... this is a strange one because it's a custom implementation but I hope it's feasible. Will start with a Diagram : 

Considering the diagram above and traffic flow from left to right, is there a way for the middle device (QinQ Capable SW most probably) to encapsulate the same Customer VLAN tagged frames (on the left) into secondary dot1Q frames, creating the QinQ frames of the scenario depicted on the right Physical Connections are as shown ... single link between devices. 

Thank you all in advance for any feedback and ideas  

[Giuseppe Larosa]

Hello @Oleksandr Y. ,

some devices may support selective QinQ tunneling where different customer VLANs subsets can be associated to a different Service Vlan tag.

A single customer C-VLAN can be associated to a single S-VLAN only , otherwise you were creating a frame multiplier and not a QinQ aware switch.

So I think that what you would like to do is not possible.

Hope to help

Giuseppe

[Oleksandr Y.]

Hi Giuseppe, thank you for the reply. 

Yes I have learned about selective QinQ as well at some point but it was not quiet what I was looking for and after further digging around I figured maybe some experts on here might have some other ideas  

I guess we will have to look into other possibilities in the meantime