Hands-On Network Programming with C

How TLS uses ciphers

Digital signatures are essential in TLS; they are used to authenticate servers. Without digital signatures, a TLS client wouldn't be able to differentiate between an authentic server and an impostor.

TLS can also use digital signatures to authenticate the client, although this is much less common in practice. Most web applications either don't care about client authentication, or use other simpler methods, such as passwords.

In theory, asymmetric encryption could be used to protect an entire communication channel. However, in practice, modern asymmetric ciphers are inefficient and only able to protect small amounts of data. For this reason, symmetric ciphers are preferred whenever possible. TLS uses asymmetric ciphers ...