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2G1325/2G5564 Practical Voice Over IP (VoIP):SIP and related protocolsSpring 2007, Period 4Lecture notes of G. Q. Maguire Jr.KTH Information andCommunication TechnologyFor use in conjunction with : Henry Sinnreich and Alan B. Johnston, InternetCommunications Using SIP: Delivering VoIP andMultimedia Services with Session Initiation Protocol,2nd Edition, Wiley, August 2006, ISBN:0-471-77657-2. 2004, 2005, 2006, 2007 G.Q.Maguire Jr. .All rights reserved. No part of this course may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission of the author.Last modified: 07.03.27Total pages: 1
Module 1: Introduction . 23Welcome to the course! . 24Staff Associated with the Course. 25Instructor (Kursansvarig) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 25Administrative Assistant: recording of grades, registration, etc. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 25Goals, Scope and Method . 26Goals of the Course - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 26Scope and Method - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 26Prerequisites.Contents .Topics .Examination requirements .Project .Assignment Registration and Report .Literature.Lecture Plan .Voice over IP (VoIP) .Potential Networks 13233343536372 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
VoIP a major market.Handsets.VoIP Chipsets .Deregulation New operators .Deregulation New Suppliers.Let them fail fast!.Latency .VOIP Modes of Operation.IP based data voice infrastructure .Voice Gateway.Voice over IP (VOIP) Gateways .Voice representation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Signaling - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Fax Support - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Management - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Compatibility - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -38394041424344454647484849494950Cisco’s Voice Over IP . 51Intranet Telephone System . 54Wireless LANs. 55Maguiremaguire@it.kth.se3 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Telia’s HomeRun.Ericsson’s "GSM on the Net" .VOIP vs. traditional telephony .Economics .VoIP vs. traditional telephony .Patents.Deregulation Trends .Carriers offering VOIP .MCI (formerly WorldCom) Connection.565758596061636465Previously - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 65Today - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 65Level 3 Communications Inc.TeliaSonera Bredbandstelefoni.Emulating the PSTN .Calling and Called Features.Beyond the PSTN: Presence & Instant Messaging.Presence-Enabled Services .Three major alternatives for VoIP .Maguiremaguire@it.kth.se666768707172734 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Negatives .Deregulation New Regulations.Regulations in Sweden .Programmable “phone” .Conferences .Not with out problems .References and Further Reading.Acknowledgements.Module 2: VoIP details.Traditional Telecom vs. Datacom.VoIP details: Protocols and Packets .RTP and H.323 for IP Telephony .RTP, RTCP, and RTSP.Real-Time Delivery .Packet delay .Dealing with Delay jitter .Delay and delay variance 586878889909192935 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Playout delay . 94When to play. 95Retransmission, Loss, and Recovery . 96Patterns of Loss . 97Loss concealment. 98VoIP need not be “toll quality” . 99RTP: Real-Time Transport Protocol. 100Payload types . 101Audio Encodings . 103Timestamps. 105Stream translation and mixing . 106RTP Control Protocol (RTCP) . 107Compound Reports . 108Proposed RTCP Reporting Extensions. 109RTP translators/mixers . 112Synchronizing Multiple Streams . 113RTP Transport and Many-to-many Transmission . 114Maguiremaguire@it.kth.se6 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Sessions, Streams, Protocol Port, and Demultiplexing .Further details of RTP and RTCP.Real Time Streaming Protocol (RTSP) .RTSP session description .References and Further Reading.115116117118119RTP and RTCP - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 121RTSP- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 124Module 3: SIP .Session Initiation Protocol (SIP) .SIP WG’s deliverables.Related working groups.125126127129Historic - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 129Session Initiation Protocol (SIP) .Is SIP simple? .SIP, RTP, and RTSP.SIP actors .SIP Methods and Status Codes .130131132133134SIP Status codes - patterned on and simular to HTTP’s status codes: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 134SIP Uniform Resource Indicators (URIs). 135Maguiremaguire@it.kth.se7 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Issues to be considered .Address Resolution.SIP timeline .SIP Invite .Bob’s response to Alice’s INVITE.ACK.SIP Invite (method/URI/version).SIP Via.Dialog (Call leg) Information .SIP CSeq.SIP Contact .SIP Content Type and Length .SIP Max-Forwards.Other header fields.Several types of SIP Servers.SIP Trapezoid .SIP Call 21431441451461471481491501511528 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
SIP Call Setup Attempt. 153SIP Call Setup Attempt. 154SIP Presence . 155SIP B not Present . 156SIP Registration Example. 157Purpose of registration. 158REGISTERing . 159SIP Call Setup Attempt. 160SIP Session Termination using BYE. 161SIP Session Termination using CANCEL. 162CANCEL and OPTIONS . 163CANCEL - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - OPTIONS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -163163Unsuccessful final responses are hop-by-hop.Authentication .SIP Method Extensions in other RFCs .SIP Extensions and Features.SIP Presence - Signed In.164165166167168Maguiremaguire@it.kth.se9 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
SUBSCRIBE and NOTIFY . 169SIP Instant Messaging Example . 170SIP Instant Messaging Example (continued). 171Message example. 172Midcall signalling . 173Call Control . 174Example of using REFER . 175QoS and Call Setup. 176SIP Message retransmission . 178RFC 3261 - Routing Changes. 179RFC 3261 - New Services . 180Compression of SIP . 181Intelligent Network service using SIP . 182Capability Set 1: Services. 183Capability Set 2 . 184Features. 185SIP development, evolution, . 191Maguiremaguire@it.kth.se10 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Gateways. 192Significance . 193References and Further Reading. 194SIP - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 194ITU Services CS-1 and CS-2 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 198Module 4: Session Annoucement Protocol (SAP) . 200Session Announcement Protocol (SAP) . 201References and Further Reading. 202SAP- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 202Module 5: Session Description Protocol (SDP) .Session Description Protocol (SDP).Session Description Protocol (SDP).SDP Message Details.Session description .SDP Offer/Response Example.SDP Response Example .Session Modification .Session modification (continued) 1311 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Start and Stop Times. 214Grouping of Media Lines in the Session Description Protocol (SDP)[74] 215Lip Synchronization . 216Next generation of SDP (SDPng) . 217SDPng structure . 218Why XML?. 219QoS and SDP . 220References and Further Reading. 221SDP- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 221Module 6: DNS and ENUM .Telephony URL and Phone-Context .SIP URL .ENUM .DNS .NAPTR - Naming Authority Pointer [88] .To find the DNS names for a specific E.164 number.ENUM Services 2 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
EUNM Timeline .Sweden’s ENUM Mapping.VISIONng Association.SIP goes beyond ENUM.References and Further Reading.235237238239240DNS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 240ENUM- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 240Module 7: SIP Mobility .SIP Mobility .Local Number Portability .References and Further Reading.245246247248SIP Mobility - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 248Service Mobility - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 248Module 8: SIP Service Creation .SIP Service Creation.Services implemented by x.Services implemented by Extensions .SIP Service Logic .Call Processing Language (CPL).Maguiremaguire@it.kth.se24925025125225325413 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
SIP Common Gateway Interface (CGI).SIP Java Servlets .JAIN APIs.US National Institute of Standards and Technology - SIP and Jain .Parlay .SIP Request-URIs for Service Control .Reason Header .Voice eXtensible Markup Language (VoiceXML ).References and Further Reading.255256257260261262263264265SIP Service Creation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - JAIN - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Parley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - SIP Request URI - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Reason Header - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - VoiceXML - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Module 9: User Preferences.User Preferences .Contact parameters .Contact header 26826927027114 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
Accept/Reject-Contact header(s) .Callee (i.e., called party) Parameter processing .Accept-Contact Example .Request-Disposition.SIP Service Examples.Privacy-Conscious Personalization .References and Further Reading.272273274275276277278User Preferences - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 278Module 10: SIP Security, NATs, and Firewalls .SIP Security .SIP Digest Authentication .SIP and S/MIME .SDP & RTP security.280281282283284Secure Call Setup [137] - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 290Efficient Stream Loss-tolerant Authentication (TESLA) .NATs and Firewalls.Types of NAT .Cone vs. Symmetric NAT .Maguiremaguire@it.kth.se29229329529615 of 222007.03.27Practical Voice Over IP (VoIP): SIP and related protocols
NAT traversal methods. 297STUN (Simple Traversal of UDP through NATs (Network Address Translation))299STUN steps. 300UDP and TCP Firewall Traversal problems. 301UDP and TCP NAT Traversal problems . 302SIP Application Level Gateway (ALG) for Firewall Traversal . 303Middlebox communications (MIDCOM) . 304Application aware Middlebox . 305Security flaws in Abstract Syntax Notation One (ASN.1) . 306Swedish Electronic Communications Act . 308Recording of Call Contents . 309Privacy & Lawful Intercept (LI). 310Reasonably Available Information . 311EU privacy and Lawful Intercept (LI) . 312Intercept architecture . 313Voice over IP Security Alliance .
2G1325/2G5564 Practical Voice Over IP (VoIP): SIP and related protocols Spring 2007, Period 4 Maguire Cover.fm Total pages: 1 maguire@it.kth.se 2007.03.27
