top level
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... starting with root, ".", immediately below which are
top level domain names such as ".com" and ".us". Below top level
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... top level domain names such as ".com" and ".us". Below top level
domain names there are normally additional levels of names.
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For example, without guidance, a site might set up some local
additional unused top level domains for testing of its local DNS code
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IANA has agreed to the four top level domain name reservations
specified in this document and will reserve them for the uses
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Confusion and conflict can be caused by the use of a current or
future top level domain name in experimentation or testing, as an
example in documentation, to indicate invalid names, or as a synonym
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The reservation of several top level domain names for these purposes
will minimize such confusion and conflict.
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