IN-ADDR.ARPA
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This document describes a way to do IN-ADDR.ARPA delegation on non-
octet boundaries for address spaces ...
... prefixes, without losing the ability to delegate
authority for the corresponding IN-ADDR.ARPA mappings. The proposed
method is fully compatible with the original DNS lookup ...
... address space) is that it seems impossible for such an organization
to maintain its own reverse ("IN-ADDR.ARPA") zone autonomously. By
use of the reverse delegation method ...
... Classless IN-ADDR.ARPA delegation ...
... delegation on to solve the problem above. These extra points
of delegation can be introduced by extending the IN-ADDR.ARPA tree
downwards, e.g. by using the first address ...
... also possible to point to an entirely different part of the DNS tree
(i.e. outside of the IN-ADDR.ARPA tree). It would be necessary to
use one of these alternate methods ...
... with no "neat" alignment of the addresses, but still wanted to
administrate their own IN-ADDR.ARPA mappings.
...
... may view this as an added bonus as no separate set of secondaries for
the reverse zone is required. Do however note that the traversal via
the IN-ADDR.ARPA tree will still be done, so the CNAME records
...
... address space, i.e. you cannot allocate a /25 prefix to one
organisation, and run IN-ADDR.ARPA this way, and then have the
organisation subnet the /25 into longer prefixes ...
... The suggested scheme gives more flexibility in delegating authority
in the IN-ADDR.ARPA domain, thus making it possible to assign address
space more efficiently without losing the ability to delegate the DNS ...