Cryptography

Once Bob’s identity is confirmed during the handshake with Alice, they no longer worry about confirming identities. Bob’s private key takes over the encryption task. Encryption prevents eaves dropping on their “conversation.”

Public Key Infrastructure (PKI) encrypts in two steps:

At the start of communication, the handshake receives extra protection. See Encrypting the handshake.
Once communication is established, encrypted data transmission begins. See Data transmission after the handshake.

Key size is directly related to security. See More about key size.