RFC 2317:Classless IN-ADDR.ARPA delegation
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... of delegation can be introduced by extending the IN-ADDR.ARPA tree downwards, e.g. by using the first address or the first address ...


... address space, to name the new zones is to use some other (non-numeric) name. Thus it is also possible to point to an entirely different part of the DNS tree (i.e. outside of the IN-ADDR.ARPA tree ...
... DNS tree (i.e. outside of the IN-ADDR.ARPA tree). It would be necessary to use one of these alternate methods if two organizations somehow ...
... IN- ADDR.ARPA tree: ...
... 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 inserted there need to point in the right direction for this to work. ...



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