performance
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... database and frequency of updates
suggest that it must be maintained in a distributed manner,
with local caching to improve performance. Approaches that
attempt to collect a consistent copy of the entire database
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In the interests of performance, implementations may couple these
functions. For example, a resolver on the same machine as a name server
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... a zero TTL prohibits caching, the realities of Internet performance
suggest that these times should be on the order of days for the typical
host. If a change can be anticipated, the ...