1. DNS/1/ゾーン/切断点

RFC 1034 に現れる単語は"zone cuts"と"each zone cut"などから分かるように、 ゾーン分割(という動作)ではなく、ゾーンの「切断点」を指す名詞である。



1.1. RFC 1034

The RRs that describe cuts around the bottom of the zone are NS RRs that name the servers for the subzones.

Since the cuts are between nodes, these RRs are NOT part of the authoritative data of the zone, and should be exactly the same as the corresponding RRs in the top node of the subzone.

Since name servers are always associated with zone boundaries,
NS RRs are only found at nodes which are the top node of some zone.

In the data that makes up a zone, NS RRs are found at the top node of the zone (and are authoritative) and at cuts around the bottom of the zone (where they are not authoritative), but never in between.

1.2. RFC 2181


6. Zone Cuts

zone cutとNSレコードの密接な関連が書かれている。-- ToshinoriMaeno 2016-03-22 23:31:41