I want to authenticate server messages to clients. The communication between clients and server is unicast. As I know I can use either used MAC or DSA.
- by using MAC, I required a shared key between client and server which can be conducted by distributing public key to the client, and the client can generate share key, encrypts it by using public key and send to the server. So I require encryption and MAC algorithms.
- by using a Digital signature, I required only distributed public key to clients.
So which one is better using DSA, or MAC and encryption?