query
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... round trips on top of the one for the original UDP query. The DNS
server also needs to keep a state of the connection ...
... transaction. Many DNS servers answer thousands of queries per
second, requiring them to use TCP will cause significant overhead ...
... security aware servers and resolvers get all the data
in Answer and Authority section in one query without truncation.
Sending Additional Data in the same query is helpful when the server
...
... Authority section in one query without truncation.
Sending Additional Data in the same query is helpful when the server
is authoritative for the data, and this reduces round trips.
...
... DNS message, resulting in a large
number of TCP query connections to the root servers. Even if all
...
... root servers. Even if all
client resolver query their local name server for information, there
are millions of these servers. Each name server ...
... message that suffers a loss of one of the fragments renders the
answer useless and the query must be retried. A TCP connection
requires a larger number of round trips ...