DNS (RFC 1034 and 1035)

1. Domain name space and resource records

   Name tree, labels and the structure of resource records.

2. Name servers and zones

   Authoritative servers, zones, delegation and caching.

3. Resolvers and resolution algorithm

   Stub and recursive resolvers and the name resolution algorithm.

4. Resource record types

   RR formats: A, NS, CNAME, SOA, MX, TXT, PTR.

5. Message format

   Header, question, answer, authority and additional sections.

6. Transport

   UDP and TCP transport, truncation and message size.

7. Clarifications to DNS

   RRSets, TTL handling and canonical names clarifications.

8. DNS over HTTPS

   Sending DNS queries and responses over HTTPS.

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