What type of encryption is used for client and server communication?

• A. RSA 2048
• B. Blowfish 56 bit
• C. AES 256
• D. TLS 1.2

Answer: (C)

The type of encryption used for client and server communication in modern applications heavily relies on the Transport Layer Security (TLS) protocol. Even though AES 256 is a strong symmetric key encryption algorithm commonly used within TLS sessions, the primary concern is the secure communication framework established by TLS itself, which provides end-to-end encryption and protects data integrity and authenticity.

TLS 1.2 is the protocol that sets the groundwork for secure communications over a network by negotiating the encryption methods and parameters to be used. Within this protocol, AES, including AES 256, can serve as the encryption algorithm for protecting the data during transit. Thus, recognizing that TLS 1.2 is the overarching framework used for secure client and server communication establishes it as the correct answer.

Using other encryption algorithms such as RSA, Blowfish, or even AES 256 alone outside of a protocol like TLS would not encompass the comprehensive security measures needed for client-server interactions, which include the negotiation of keys and secure connections.