Networking › Module 3 › Lesson 2
HTTP vs HTTPS
Ports 80 and 443, and why TLS changed the web
Opening
Plaintext vs encrypted web traffic
HTTP built the early web—but it sends pages, cookies, and login forms in readable plaintext. HTTPS wraps HTTP inside TLS so attackers on the same network cannot easily read or tamper with your session.
1. HTTP — Port 80
HTTP (Hypertext Transfer Protocol) is the application-layer language browsers and servers use for web pages and APIs. Default port: 80 URL prefix: http:// On untrusted Wi-Fi, anyone sniffing traffic can see URLs, form data, and session cookies. Most legitimate sites now redirect HTTP to HTTPS—but legacy systems and misconfigurations still expose port 80.
2. HTTPS — Port 443
HTTPS is HTTP plus TLS (Transport Layer Security). TLS encrypts data in transit and helps verify you reached the real server. Default port: 443 URL prefix: https:// The TLS handshake negotiates cipher suites, authenticates the server certificate, and establishes session keys. Modern browsers flag sites without HTTPS as "Not Secure."
3. What TLS Protects (and What It Does Not)
Protects
Confidentiality and integrity of data between client and server on the wire.
Does not prove trust
A phishing site can have a valid certificate—HTTPS only secures the connection, not the site owner.
Defender use
Inspect TLS versions and cipher suites during audits; block weak protocols at the firewall.
Certificate warnings matter
If a browser warns that a certificate is invalid or mismatched, do not click through. It may indicate a man-in-the-middle attack or a misconfigured server.
Knowledge Check
Which port is the default for HTTPS?
Multiple choice
Knowledge Check
TLS on HTTPS primarily provides:
Multiple choice
Knowledge Check
HTTP traffic on port 80 is risky on public Wi-Fi because:
Multiple choice