What encryption algorithm is used to ensure the security of the HTTPS protocol?

To ensure the security of the HTTPS protocol, a combination of encryption algorithms is used, but the key component is the use of the TLS (Transport Layer Security) protocol, which employs asymmetric encryption for key exchange and symmetric encryption for data transfer.

Main algorithms:

• For key exchange: RSA, Diffie-Hellman (including ECDH — elliptic curve)
• For symmetric encryption: AES (Advanced Encryption Standard) — the most common
• For hashing and integrity verification: SHA-2 (e.g., SHA-256)

Thus, HTTPS uses a hybrid approach: first, an asymmetric encryption establishes a shared secret key, and then a fast symmetric algorithm AES is used for data transfer.

Example: the client and server agree on a key using ECDHE, then all traffic is encrypted with AES-256.