Ray Bellis wrote:
where even telephone switches (thus, telephone operators) do not have
any knowledge on how many numbers should be dialed.
It is for this reason that Send-N specifies the _minimum_ number of
required digits, not the exact number.
It contradicts with the following description of the draft:
this information, the application is not required to query the DNS
every time a new digit is dialed, but can wait to collect sufficient
digits to receive a response.
That is, the application can wait to collect sufficient digits to
know the _minimum_ number means that the application MUST know
the minimum number of digit to make such query, even though E.164
structure often changes.
Worse, even if the application knows the _minimum_ number, the
application MUST make DNS querys for every digit beyond the
_minimum_ number, which means negligibly small number of queries
could be saved.
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