Encryption in 3.5 GHZ frequency

Guys,
I had a small debate the other day with one of our Wireless vendors. He came to install 3.5 GHZ microwave antenna and so i happened to question him as to what encryption do they use to securing data communication happening between two antennas. His answer was you dont require any encryption for this kind of connectivity as 3.5 GHZ is not free and so not open to anyone. Its a licensed band which i too agree but what i didnt agree was that of no encryption required, there has to be some kind of encryption set for secure communication isnt it?? or was the vendor correct in saying that you dont need any encryption for licensed band.