Suppose that Sally (a server) needs access to a symmetric key for user Alice and another symmetric key for Bob and another symmetric key for Charlie. Then Sally could generate symmetric keys K a ±, K...

Suppose that Sally (a server) needs access to a symmetric key for user Alice and another symmetric key for Bob and another symmetric key for Charlie. Then Sally could generate symmetric keys K_a±, K_B, and K_c
and store these in a database. An alternative is key diversification, where Sally generates and stores a single key K_s- Then Sally generates the key K_A
as needed by computing K_A
= /i(Alice, K_s), with keys K_B
and K_c
generated in a similar manner. Give one significant advantage and one significant disadvantage of key diversification as compared to storing keys in a database.