Consider consolidating subsections for each Resource Record definition

[vttale]

Sections 5, 6, and 7, defining the NSEC5KEY, NSEC5, and NSEC5PROOF RRs respectively, could be tightened up by not using subsections for wire format and presentation format. Of course, each record would still have its own section.

The subsections break up the flow and, while convenient for external references, are also not really long enough that someone following an external reference that intended to focus on, say, presentation format, would have trouble finding what they were looking for in each consolidated section.

[vttale]

Relatedly, typographically it is kind of weird that lines like "The presentation format of the NSEC5 RDATA is as follows:" end in a colon that introduces paragraphs. I'd make them some kind of list, probably definition lists.