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Glossary · DNS

DNS over TLS

Sending DNS queries over a TLS-encrypted TCP connection to port 853 (RFC 7858), protecting lookups between a client and its resolver.

What it means

DNS over TLS encrypts the link between a client, such as a phone or mail server, and its recursive resolver, using a dedicated port, 853. RFC 7858 defines it.

It and DNS over HTTPS solve the same problem, privacy of queries on the network, in different ways: DoT is a distinct port that networks can see and manage, DoH blends into HTTPS. Neither proves the answer is authentic; that is what DNSSEC does.

A mail server can use DoT to reach a resolver outside its own network.

Sources

What this definition rests on. The wording is ours; the facts are theirs.

All 432 terms in the glossaryThe wiki: blocklists and bounce codes

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