{"id":1211,"date":"2011-07-28T23:13:38","date_gmt":"2011-07-28T23:13:38","guid":{"rendered":"https:\/\/www.techopedia.com\/definition\/session-initiation-protocol\/"},"modified":"2012-11-14T10:12:02","modified_gmt":"2012-11-14T10:12:02","slug":"session-initiation-protocol","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip","title":{"rendered":"Session Initiation Protocol"},"content":{"rendered":"<h2><span id=\"what_does_session_initiation_protocol_mean\">What Does Session Initiation Protocol Mean?<\/span><\/h2>\n<p>Session Initiation Protocol (SIP) is a text-based signaling protocol that establishes Internet Protocol (IP) network sessions at the application layer. Signaling protocols are used for signaling encapsulation identification.<\/p>\n<p>SIP was designed in 1996 and approved by the Internet Engineering Task Force (IETF). RFC 3261 is the most current version.<\/p>\n<h2><span id=\"techopedia_explains_session_initiation_protocol\">Techopedia Explains Session Initiation Protocol<\/span><\/h2>\n<p>SIP is used in applications ranging from Unicast Voice Over Internet Protocol (VoIP) calls to multistream or multimedia conferencing. SIP runs on User Datagram Protocol (UDP), Stream Control Transmission Protocol (SCTP) or Transmission Control Protocol (TCP).<\/p>\n<p>SIP was accepted as a 3rd Generation Partnership Project (3GPP) signaling protocol in November 2000 and became a permanent component of IP Multimedia Subsystem (IMS), which is a mobile (cellular) multimedia streaming framework.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>What Does Session Initiation Protocol Mean? Session Initiation Protocol (SIP) is a text-based signaling protocol that establishes Internet Protocol (IP) network sessions at the application layer. Signaling protocols are used for signaling encapsulation identification. SIP was designed in 1996 and approved by the Internet Engineering Task Force (IETF). RFC 3261 is the most current version. [&hellip;]<\/p>\n","protected":false},"author":7813,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","format":"standard","meta":{"_acf_changed":false,"_lmt_disableupdate":"","_lmt_disable":"","om_disable_all_campaigns":false,"footnotes":""},"definitioncat":[245,219],"class_list":["post-1211","definition","type-definition","status-publish","format-standard","hentry","definitioncat-internet","definitioncat-networks"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v24.2 (Yoast SEO v24.5) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>What is Session Initiation Protocol (SIP)? - Definition from Techopedia<\/title>\n<meta name=\"description\" content=\"This definition explains the meaning of Session Initiation Protocol and why it matters.\" \/>\n<meta name=\"robots\" content=\"noindex, follow\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Session Initiation Protocol\" \/>\n<meta property=\"og:description\" content=\"This definition explains the meaning of Session Initiation Protocol and why it matters.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip\" \/>\n<meta property=\"og:site_name\" content=\"Techopedia\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/techopedia\/\" \/>\n<meta property=\"article:modified_time\" content=\"2012-11-14T10:12:02+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:site\" content=\"@techopedia\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip\"},\"author\":{\"name\":\"Margaret Rouse\",\"@id\":\"https:\/\/www.techopedia.com\/#\/schema\/person\/f5dd538e31ee352d105b8af36c4268a5\"},\"headline\":\"Session Initiation Protocol\",\"datePublished\":\"2011-07-28T23:13:38+00:00\",\"dateModified\":\"2012-11-14T10:12:02+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip\"},\"wordCount\":129,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.techopedia.com\/#organization\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip#respond\"]}],\"articleSection\":\"\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip\",\"url\":\"https:\/\/www.techopedia.com\/definition\/421\/session-initiation-protocol-sip\",\"name\":\"What is Session Initiation Protocol (SIP)? 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