lookup
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... SIP trapezoid
It is important to note that DNS lookups can be used multiple times
throughout the processing of a call. In general, an element that
...
... caller initiates a call until the time the called party is
alerted should be no more than a few seconds. Given that there can
be multiple hops, each of which is doing DNS lookups in addition to
other potentially time-intensive operations, the amount of time
available for DNS lookups ...
... DNS lookups in addition to
other potentially time-intensive operations, the amount of time
available for DNS lookups at each hop is limited.
Scalability ...
... URI (i.e., the URI is not rewritten with the
result of the DNS lookup), they only result in an IP address, port
...
... TCP will be used, targeted to a host determined by an SRV lookup of
_sip._tcp.example.com. That lookup would return:
...
... SRV lookup of
_sip._tcp.example.com. That lookup would return:
;; Priority Weight Port Target ...
... proxy, redirect server, or registrar is to be contacted
through the lookup of NAPTR records, there MUST be at least three
records - one with a "SIP ...
... 2543(-> 3265prop | 3264prop | 3263prop | 3262prop | 3261prop). It specified that a client would
lookup SRV records for all transports it supported, and merge the
...
... URI, the client performs an A or AAAA record lookup of the domain
name. The result will be a list of IP addresses, each of which can
...
... client performs an A or AAAA record
lookup of the domain name. The result will be a list of IP
addresses, each of which can be contacted using the transport
protocol ...