Networked Multimedia ServicesIntroductionFunctional CharacteristicsPerformance CharacteristicsSummaryProblemsBasic Session Initiation ProtocolIntroductionTerminologyMultimedia SessionSession Initiation ProtocolSIP Request MessagesSIP Response MessagesSIP Call and Media Trapezoid OperationSIP Header FieldsSIP TagsSIP Option TagsSIP Media Feature TagsSummaryProblemsSIP Message ElementsIntroductionCanceling a RequestRegistrationIndicating UA CapabilitiesDiscovering UA and Proxy CapabilitiesDialogsInitiating a SessionModifying an Existing SessionHandling Message BodyTerminating a SessionProxy BehaviorTransactionsTransportSummaryProblemsAddressing in SIPIntroductionSIP Public AddressGlobally Routable UA URIServices URISummarySIP Event Framework and PackagesIntroductionEvent FrameworkEvent PackageSummaryProblemsPresence and Instant Messaging in SIPIntroductionSIP PresenceSIP Instant MessagingSummaryProblemsMedia Transport Protocol and Media NegotiationIntroductionReal-Time Transmission and Control ProtocolSecure RTP (SRTP)ZRTPReal-Time Streaming Protocol (RTSP)Media Resource Control Protocol (MRCP)Session Description Protocol (SDP)SummaryProblemsDNS and ENUM in SIPIntroductionDomain Name SystemENUMDSN and ENUM SecuritySummaryProblemsRouting in SIPIntroductionSIP RegistrarSIP ProxyTraversing a Strict-Routing ProxyRewriting Record-Route Header Field ValuesRecord-Routing with Globally Routable UA URIDouble Route-RecordTransport Parameter Usage Problems and RemediesCaller Preferences-Based RoutingLocation-Based RoutingLoop DetectionSummaryProblemsUser and Network-Asserted Identity in SIPIntroductionMultiple User IdentitiesPublic User IdentityPrivate User IdentityNetwork-Asserted IdentitySummaryProblemsEarly Media in SIPIntroductionEarly Media and Session Establishment in SIPEarly-Media Solution ModelsEarly-Media Solution Model with Disposition-Type: Early-SessionEarly-Media Solution Model with P-Early-Media HeaderSummaryService and Served-User Identity in SIPIntroductionCommunications Service IDAsserted- and Preferred-Service IDServed-User ID for Handling ServicesSummaryProblemsConnections Management and Overload Control in SIPIntroductionConnections Management in SIP NetworkLoss-Based Overload Control in SIP NetworkRate-Based Overload Control in SIP NetworkSummaryProblemsInterworking Services in SIPIntroductionSIP Session Border ControllerNAT Crossing by SIPSIP-PSTN/ISDN Protocols InterworkingSummaryProblemsResource Priority and Quality of Service in SIPIntroductionCommunications Resource Priority in SIPPreemption Events in SIPQOS in SIPSDP Media Streams Mapping to QOS FlowsQOS Mechanism Selection in SDPSIP Signaling CompressionSummaryProblemsCall Services in SIPIntroductionCall Transfer and Related Call ServicesCall Diversion IndicationCall Services Using Session Border ControllerReferring Call to Multiple ResourcesCall Services with Content IndirectionTranscoding Call ServicesINFO Method-Mid-Call Information TransferSIP Call Control UUI Transfer ServicesCall Services Using DTMFEmergency Call Services in SIPMedia Server Interfaces in SIPIntroductionSIP Interface to VoiceXML Media ServerSummaryProblemsMultiparty Conferencing in SIPIntroductionMultiparty Multimedia ConferencingThird-Party Multiparty ConferencingSummaryProblemsSecurity Mechanisms in SIPIntroductionMultilevel Security Characteristics in SIPSecurity Mechanisms NegotiationAuthentication in SIPAuthorization in SIPIntegrity and Confidentiality in SIPSecurity for SIP URI-List ServicesConsent-Based Communications for Enhancing Security in SIPSIP Forking Proxy SecurityNonrepudiation Services in SIPCall Flows Explaining SIP Security FeaturesThreat Model and Security Usage Recommendations in SIPSummaryProblemsPrivacy and Anonymity in SIPIntroductionPrivacy Mechanism in SIPAsserted and Preferred Identity for Privacy in SIPConnected Identity for Privacy in SIPGuidelines for Using Privacy Mechanism in SIPAnonymity in SIPSummaryProblemsAppendix A: ABNFAppendix B: Reference RFCs