update
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... RFC1034], [RFC1035], and the subsequent documents that
update them; particularly, [RFC2181] and [RFC2308].
...
... NSEC RRsets are REQUIRED at that name. A KEY RRset at that
name for secure dynamic update purposes is also allowed ([RFC3007]).
Other types MUST NOT be present at that name.
...
... must be aware that the answers received may not be sufficient to
validate the original response. For example, a zone update may have
changed (or deleted) the desired information between the original and
...
... query and the expiration of the data from the cache, the
authoritative data might have been changed (for example, via dynamic
update).
There are two situations for which this is relevant:
...
... Wellington, B., "Secure Domain Name System (DNS) Dynamic Update", RFC 3007prop, November 2000. ...