UDP
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... SIP can run over a variety of transport
protocols, including TCP, UDP, and SCTP. SIP can also use TLS ...
... TCP for a SIPS URI. This is
because UDP is the only mandatory transport in RFC 2543(-> 3265prop | 3264prop | 3263prop | 3262prop | 3261prop) [6 ...
... transport protocol supported by the domain. This
specification defines D2U for UDP, D2T for TCP, and D2S for SCTP. We
...
... in that order of preference. Since the client supports TCP and UDP,
TCP will be used, targeted to a host ...
... client SHOULD use TCP for a SIPS
URI, and UDP for a SIP URI. However, another transport protocol,
...
... transport failure of some sort (generally,
due to fatal ICMP errors in UDP or connection failures in TCP).
...
... 1] defines procedures for sending responses from a server
back to the client. Typically, for unicast UDP requests, the
response is sent back to the source IP address where the request came
...