|English: The Google HTTPS logo Italiano: Il logo di Google HTTPS (Photo credit: Wikipedia)|
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Here are the main purposes of secure protocols over the Internet and other media.
- Guarantee non-repudiation –
- Know who I am talking to:
- Identity validated through certificates
- Prevent identity usurpation by malicious third parties
- Prevent man in the middle attacks
- Know that I have received what my interlocutor really sent
- Information integrity validated
- Ensure that third parties cannot understand the information flows –Prevent sniffing
The concept of legal interception is important: most state require the ability to intercept any communication from their citizen based on a legal decision. As in many countries, justice depends directly from the government, you are only a little bit safer with HTTPS.
You should be aware of the limitations of HTTPS:
- the TLS SNI extension permits any man in the middle to know which domains you have browsed and how frequently,
- DNS queries reveal also the domains you have browsed.