Imagine Bob's office is connected via a (quantum-)encrypted connection to a server. How could Bob access this server from his home office if he does not have the necessary hardware at home? Well, he could get keys in his office and save them on his personal key-safe token. He could subsequently use the token at home and connect to the server.

The topic of offline distribution of cryptographic keys is interesting for researchers and practitioners alike, even outside the QKD context. Your thesis would evolve around the evaluation of already existing consumer devices that could be used to store and transport QKD-keys (or symmetric cryptographic keys in general).