SIP: Understanding the Session Initiation Protocol

309 Pages·2003·2.45 MB·English

by  Alan B. Johnston

SIP
Understanding the Session Initiation Protocol
SecondEdition
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SIP
Understanding the Session Initiation Protocol
SecondEdition
Alan B. Johnston
Artech House
Boston • London
www.artechhouse.com
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Johnston,AlanB.
SIP:UnderstandingtheSessionInitiationProtocol.—2nded.—(ArtechHouse
telecommunicationslibrary)
1.Computernetworkprotocols
I.Title
004.6’2
ISBN1-58053-655-7
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Contents
ForewordtotheFirstEdition xvii
PrefacetotheSecondEdition xix
PrefacetotheFirstEdition xxi
1 SIPandtheInternet 1
1.1 SignalingProtocols 1
1.2 TheInternetEngineeringTaskForce 2
1.3 ABriefHistoryofSIP 3
1.4 InternetMultimediaProtocolStack 4
1.4.1 PhysicalLayer 4
1.4.2 InternetLayer 4
1.4.3 TransportLayer 5
1.4.4 ApplicationLayer 8
1.5 UtilityApplications 9
1.6 DNSandIPAddresses 10
1.7 URLsandURIs 12
1.8 Multicast 12
1.9 ABNFRepresentation 13
References 14
vii
viii SIP:UnderstandingtheSessionInitiationProtocol
2 IntroductiontoSIP 17
2.1 ASimpleSessionEstablishmentExample 17
2.2 SIPCallwithProxyServer 25
2.3 SIPRegistrationExample 31
2.4 SIPPresenceandInstantMessageExample 33
2.5 MessageTransport 38
2.5.1 UDPTransport 38
2.5.2 TCPTransport 40
2.5.3 TLSTransport 40
2.5.4 SCTPTransport 41
References 42
3 SIPClientsandServers 43
3.1 SIPUserAgents 43
3.2 PresenceAgents 44
3.3 Back-to-BackUserAgents 45
3.4 SIPGateways 45
3.5 SIPServers 47
3.5.1 ProxyServers 47
3.5.2 RedirectServers 52
3.5.3 RegistrationServers 55
3.6 AcknowledgmentofMessages 55
3.7 Reliability 56
3.8 Authentication 57
3.9 S/MIMEEncryption 59
3.10 MulticastSupport 60
3.11 FirewallsandNATInteraction 61
3.12 ProtocolsandExtensionsforNATTraversal 62
3.12.1 STUNProtocol 63
3.12.2 TURNProtocol 65
3.12.3 OtherSIP/SDPNAT-RelatedExtensions 66
References 68