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Beginner · Lessons: 4

DNS: the internet’s address book

How names become addresses, who sees your lookups, and how encrypted DNS changes that.

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  1. 1 What DNS does

    Why computers need a name-to-number lookup for every website you visit, and who actually answers that lookup.

    6 min
  2. 2 Who sees your DNS lookups

    A plain DNS lookup travels unencrypted. Here is exactly who is positioned to read it, and why that matters even on an HTTPS site.

    6 min
  3. 3 Encrypted DNS: DoH and DoT

    Two standards wrap DNS lookups in encryption. What that actually hides, what it still does not, and how macOS supports it.

    7 min
  4. 4 DNS in attacks and defence

    The same lookup that gets you to a website is also used to fool you into the wrong one, to block sites, and, occasionally, to smuggle data out. What to watch for.

    7 min

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