When visiting a website, students are often told to “look for the padlock.” In IB Computer Science, that padlock represents HTTPS, the protocol that allows websites to communicate securely. Students are expected to understand what HTTPS is, why it is used, and how it protects data during transmission.
IB examiners focus on conceptual understanding, not low-level protocol details.
What Is HTTPS?
HTTPS (HyperText Transfer Protocol Secure) is a secure version of HTTP.
HTTPS:
- Encrypts data sent between a browser and a web server
- Protects data from interception
- Verifies website identity
In IB terms, HTTPS provides:
- Confidentiality
- Integrity
- Authentication
Why HTTP Alone Is Not Secure
Standard HTTP:
- Sends data in plaintext
- Can be intercepted by attackers
- Does not verify website identity
This means:
- Passwords can be stolen
- Data can be modified
- Users can be redirected to fake websites
HTTPS exists to solve these problems.
How HTTPS Works (Conceptually)
HTTPS combines:
- Encryption
- Digital certificates
- Public Key Infrastructure (PKI)
The process works conceptually as follows:
