hello-dns/rare.md

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                        **A warm welcome to DNS**

Note: this page is part of the 'hello-dns' documentation effort.

Rare

DNS is currently described in over 150 RFCs. Not all of these are operational, and it is uncertain if all of them should be.

This page is a menu of things that are specified, but not in wide production.

Standards listed here could be omitted from 2018 implementations without causing operational problems, but this may change in the future.

Applicable to authoritative servers:

• TKEY
• SIG(0)