A set of RRs with a specified NAME and TYPE exists and has the same members with the same RDATAs as the RRset specified here in this section. While RRset ordering is undefined and therefore not significant to this comparison, the sets be identical in their extent.
For this prerequisite, a requestor adds to the section an entire RRset whose preexistence is required. NAME and TYPE are that of the RRset being denoted. CLASS is that of the zone. TTL must be specified as zero (0) and is ignored when comparing RRsets for identity.