Root Zone
The top of the DNS hierarchy, published by IANA, listing every TLD and the nameservers authoritative for it.
The root zone is the tiny but critically important file at the top of DNS. It contains a single entry per TLD (`.com`, `.uk`, `.xyz`, etc.) pointing at that TLD's authoritative nameservers, plus the DNSSEC keys that anchor the whole chain of trust. It is published by IANA and served by the 13 root server letters (A through M), each operated by a different organisation and replicated globally via anycast to hundreds of physical locations. Every recursive resolver on Earth has the root server addresses baked in and starts here when its cache is cold.
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Referenced on
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