Why HTTPS Beats HTTP: Key Differences in Security, Authentication, and Performance

Security Difference

HTTP is an insecure protocol that transmits data in plaintext, making it vulnerable to eavesdropping and tampering, and therefore unsuitable for sensitive information such as bank cards, usernames, and passwords.

HTTPS adds a security layer by using SSL/TLS to encrypt data packets, providing higher security that makes it difficult for malicious users or hackers to intercept or modify the data.

Authentication Difference

Using HTTPS requires obtaining a digital certificate from a Certificate Authority (CA). Websites with SSL certificates display a lock icon and the "https" prefix.

The CA packages the holder's public key, usage, issuer, and validity period, computes a hash, signs it with its private key to create a Certificate Signature, and attaches this signature to the certificate, forming a digital certificate.

HTTPS uses the digital certificate to authenticate the server, ensuring the client connects to the intended server and protecting against man‑in‑the‑middle attacks, whereas HTTP provides no server authentication.

Encryption Difference

HTTP transmits data without encryption, leaving it in plaintext.

HTTPS employs TLS/SSL encryption, so only the client and server can decrypt and understand the transmitted data.

Port Difference

HTTP typically uses port 80 for communication.

HTTPS typically uses port 443 for communication.

Performance Difference

Because it does not involve encryption and decryption, HTTP generally offers higher performance.

HTTPS incurs additional computational overhead for encryption and decryption, resulting in slightly lower performance.

In summary, HTTPS combines SSL with HTTP to provide encrypted transmission and server authentication, making it far more secure than plain HTTP.