RDC version 7.1 vs. RDC version 8.1

Hello,

I have new 2012 RDS enviornments with 2012 r2 gateways and 2012 session host. From Windows 7 machines, Ive been telling customers to use the latest client RDC 8.1 which works great. It wont work with RDC 7.1 which is fine.

Besides new features in the new clients and in windows 2012 R2, is there a scenario where rdc 7.1 might work connecting through a 2012 R2 gateway?

I was just curious as to exactly why 7.1 will not work. Is it just the new features, or does it have to with crypto as well?

I was thinking it might have to do with 7.1 using RPc over HTTP and 2012 R2 doesnt do that anymore.

Thanks