alert

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disposition 型 alert (SIP)

[3] RFC 3261 - SIP: Session Initiation Protocol (2014-08-15 14:48:03 +09:00 版) <http://tools.ietf.org/html/rfc3261#section-14.1>
[1] RFC 3261 - SIP: Session Initiation Protocol (2014-08-15 14:48:03 +09:00 版) <http://tools.ietf.org/html/rfc3261#section-20.11>
[2] RFC 3261 - SIP: Session Initiation Protocol (2014-08-15 14:48:03 +09:00 版) <http://tools.ietf.org/html/rfc3261#section-27.6>