Computer Networking Basics
Which of the following does HTTPS (HTTP protected by TLS) protect?
- AThat the operator of the website you connect to is a trustworthy person or organization without malicious intent
- BThat the fact you are communicating, and the IP address of the server you connect to, cannot be seen along the path
- CThat the content cannot be read or altered in transit, and that the server you connect to is the legitimate holder of the domain name in its certificate
Show answer and explanation
Answer: C. That the content cannot be read or altered in transit, and that the server you connect to is the legitimate holder of the domain name in its certificate
TLS provides three things: encryption of the communication (confidentiality), detection of tampering (integrity) and authentication of the server. The server presents a certificate, and the browser checks it by following signatures back to a certificate authority (CA) it trusts and confirms that it matches the domain name in the URL. What this proves, however, is only that you are talking to the holder of that domain name; it says nothing about whether the site's operator is honest. Even a scam site can obtain a certificate for its own domain. Also, the IP header is not encrypted, so which IP address you talk to, when and how much can be seen along the path.
- A. A certificate only shows who holds the domain name; it does not vouch for the operator's honesty.
- B. The IP header is not encrypted, so the peer's address and the traffic volume are visible.
- C. Correct. Confidentiality, integrity and server authentication are what TLS provides.