What is the function of the asymmetric-key-encryption algorithm in SSL-based PKI solutions?

The function of the asymmetric-key encryption algorithm in SSL-based Public Key Infrastructure (PKI) solutions primarily revolves around encrypting the symmetric key. In SSL/TLS protocols, asymmetric encryption is used during the initial handshake process to securely exchange a symmetrical key, which is then used to encrypt the actual data transmitted between the client and server.

During this handshake, the server sends its public key to the client. The client then generates a random symmetric key, which is encrypted using the server's public key and sent back to the server. Since only the server can decrypt this message using its corresponding private key, the symmetric key remains secure during transit. After this key exchange, symmetric encryption is utilized for the duration of the session to efficiently encrypt all data due to its speed and lower computational requirements.

In summary, the primary role of asymmetric encryption in this context is to securely facilitate the exchange of the symmetric key, which is later used for encrypting the data itself. Other options do not accurately represent the specific function of asymmetric key encryption within SSL-based PKI solutions.