Connection security

HTTP, HTTPS & TLS

Many websites still use HTTP. HTTPS with modern TLS protects the connection between a visitor and a website.

Comparison of HTTPS and HTTP browser connection indicators
To explain it simply: HTTPS encrypts information in transit, while HTTP does not. Browser icons vary, and HTTPS does not by itself prove that a website is trustworthy.

HTTP

Typical port: 80

⚠ No TLS encryption

Traffic can be read or changed by an attacker on an unsafe network. Browsers may show “Not Secure”.

HTTPS

Typical port: 443

🔒 HTTP running over TLS

TLS encrypts traffic and helps the browser verify that it reached the expected domain.

Port 443 is not the security protocol

Port 443 is the conventional HTTPS port. The protection comes from TLS, not from the port number itself.

TLS 1.2 / TLS 1.3
        ↓
Encryption
        ↓
      HTTPS

TLS is not SSL

ProtocolStandardizedWidely adoptedStatus
SSL 2.019951990sObsolete
SSL 3.01996Late 1990sObsolete
TLS 1.01999Early 2000sObsolete
TLS 1.12006Limited adoptionObsolete
TLS 1.220082014–2016Supported
TLS 1.320182019–2021Modern

Check a real TLS connection with OpenSSL

This establishes a TLS connection to the server and reports the negotiated protocol and cipher.

openssl s_client -connect boards.pig.kr:443 -tls1_2

Example result:

Protocol  : TLSv1.2
Cipher    : ECDHE-ECDSA-AES256-GCM-SHA384

The simplest way to remember it

80  → HTTP  → ⚠ Not Secure

443 → HTTPS → TLS → 🔒 Secure

The number 443 is not what makes a connection secure. TLS is what makes HTTPS secure.