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Voice Over IP

Book Description


2246C-4

The authoritative guide to Internet telephony

  • Managing and optimizing the performance of IP voice networks

  • Configuring IP-based call centers

  • Internetworking IP with SS7

  • Uyless Black has written the essential guide for telecommunications professionals who must understand voice-over-IP (VoIP)-or deploy it. Clearheaded and free of hype, Voice Over IP carefully evaluates both VoIP's challenges and its compelling advantages, and then reviews each technical standard and critical issue associated with successful deployment.

    Start by reviewing the key Internet and IP characteristics that make VoIP difficult, including packet loss and variable delay. Next, understand the role of digital signal processors (DSPs) and voice coders in VoIP. Learn how to establish paths to service providers through the local loop via ISDN, xDSL, HFC, or other approaches; review modem technology for VoIP applications; and understand today's key Internet telephony protocols. Coverage includes:

  • Integrating total VoIP solutions: DSPs, voice coders, high-speed modems, gateways, local loop connectivity, and more

  • The role of VoIP gateways and gatekeepers

  • Internetworking SS7 with IP and H.323

  • VoIP supporting protocols for multicasting (IGMP and MBONE), bandwidth reservation (RSVP, RTP, RTCP), and security services

  • Black describes today's best approaches for managing performance in both private and public IP networks, compares VoIP with packet voice alternatives such as Voice over Frame Relay (VoFR) and Voice over ATM (VoATM), and more. You'll also find convenient references to telephony signaling, ISDN and SS7, and V.90 modems.

    Every telecommunications professional will be impacted by the VoIP revolution. Whether you're evaluating or deploying VoIP, this book places a world-class telecom consultant at your side, delivering all the objective information and insight you need to succeed.

    Table of Contents

    1. Copyright
    2. Preface
    3. Introduction
      1. INTERNET TELEPHONY AND PACKETIZED VOICE
      2. WHY INTERNET TELEPHONY?
      3. WHY USE IP FOR TELEPHONY TRAFFIC?
      4. BARRIERS TO SUCCESSFUL DEPLOYMENT OF IP TELEPHONY
      5. VoIP IN THE INTERNET AND IN PRIVATE INTERNETS
      6. THE QUESTION: NOT IF, BUT HOW?
      7. CONFIGURATION OPTIONS
      8. PRIVATE VoIP NETWORKS
      9. THE NEXT STEP
      10. E-COM AND IP-BASED CALL CENTERS
      11. CONFIGURATION AND TOPOLOGY CHOICES
      12. BASIC TERMS AND CONCEPTS
      13. ATTRIBUTES OF THE INTERNET
      14. THE INTERNET LAYERED ARCHITECTURE
      15. EVALUATING THE FACTORS IN PACKETIZED VOICE
      16. ACCOMMODATING TO THE VOICE AND DATA REQUIREMENTS IN A NETWORK
      17. MAKING THE INTERNET LOOK LIKE THE TELEPHONE NETWORK
      18. Summary
    4. Characteristics of the Internet and IP
      1. ARCHITECTURE OF AN INTERNET
      2. ISPs AND THE TELEPHONE NETWORK
      3. ATTRIBUTES OF THE INTERNET
      4. PACKET LOSS
      5. NEED FOR FIXED ROUTING?
      6. SIZE OF PACKETS AND KINDS OF TRAFFIC IP SUPPORTS
      7. OVERVIEW OF IP
      8. TCP AND UDP
      9. SUMMARY
    5. Digital Signal Processors (DSPs)
      1. ROLE OF DSPS IN PACKET-VOICE OPERATIONS
      2. DSP VS. CUSTOMIZED HARDWARE
      3. FIXED- AND FLOATING-POINT PROCESSORS
      4. MEMORY ARCHITECTURES
      5. THE SOFTWARE IS DIFFERENT
      6. FAST FOURIER TRANSFORM (FFT) OPERATIONS
      7. SIGNAL FILTERS AND THE FINITE IMPULSE RESPONSE (FIR) FILTER
      8. PREDICTABILITY OF PERFORMANCE
      9. ANOTHER EXAMPLE OF DSP CODE
      10. COMING UP
      11. SUMMARY
    6. Voice Coders
      1. FUNCTIONS OF THE VOICE CODER
      2. CLASSIFICATION OF SPEECH CODERS
      3. LINEAR PREDICTION ANALYSIS-BY-SYNTHESIS (LPAS) CODERS
      4. PARAMETER SPEECH CODERS: 2.4-KBIT/S MIXED-EXCITATION LPC (MELP)
      5. EVALUATING CODERS
      6. COMPARISON OF SPEECH CODERS
      7. SUMMARY
    7. Connecting to Service Providers through the Local Loop
      1. PATH BETWEEN AN INTERNET USER AND THE INTERNET
      2. THE BANDWIDTH PROBLEM AT THE LOCAL LOOP
      3. TERMINATING THE MODEM ANALOG SIGNAL
      4. ALTERNATIVES TO THE MODEM-BASED LOCAL LOOP ACCESS
      5. THE INTEGRATED SERVICES DIGITAL NETWORK (ISDN)
      6. ROLE OF DIGITAL SUBSCRIBER LINE (DSL) TECHNOLOGIES
      7. THE HYBRID/FIBER COAX (HFC) APPROACH
      8. A HIGH-SPEED PROPRIETARY SOLUTION
      9. BYPASSING THE CIRCUIT-SWITCHED TECHNOLOGY TO REACH THE INTERNET
      10. SUMMARY
    8. Modems, LAPM, PPP, and the V.100 Series
      1. ANOTHER LOOK AT THE LAYERED ARCHITECTURE FOR VoIP
      2. PREVALENT MODEMS
      3. ROLE OF DSPS IN THE MODEM'S OPERATIONS
      4. TYPICAL LAYOUT
      5. V.24
      6. THE EIA-232 INTERFACE
      7. TYPICAL LAYOUT FOR THE MODEM
      8. ROLE OF THE POINT-TO-POINT PROTOCOL (PPP)
      9. THE PROTOCOL DATA UNIT ON THE LINK BETWEEN THE USER AND THE ISP
      10. V SERIES MODEMS
      11. THE 56 KBIT/S MODEM (V.90)
      12. THE V.110 AND V.120 RECOMMENDATIONS FOR ISDN INTERFACES
      13. V.120
      14. SUMMARY
    9. Putting the Pieces Together
      1. YET ANOTHER LOOK AT THE LAYERED ARCHITECTURE FOR VoIP
      2. STEPS TO THE EXCHANGE OF VOIP TRAFFIC
      3. ANOTHER LOOK AT THE VoIP PROTOCOL SUITE
      4. THE VoIP TUNNEL
      5. UNDUE PROCESSING OVERHEAD
      6. SUMMARY
    10. Performance Considerations
      1. PACKET SIZE, BUFFER SIZE, LOSS, AND LATENCY
      2. PERFORMANCE OF VoIP IN PRIVATE SYSTEMS
      3. PERFORMANCE OF VoIP IN PUBLIC SYSTEMS
      4. SUMMARY
    11. VoIP Gateways and Gatekeepers
      1. THE GATEWAY/GATEKEEPER MODEL
      2. THE H.323 SPECIFICATION
      3. ARCHITECTURE OF H.323
      4. CODEC REQUIREMENTS
      5. THE H.323 PROTOCOL STACK
      6. REGISTRATION, ADMISSIONS, AND STATUS (RAS) OPERATIONS
      7. OTHER RAS PROCEDURES
      8. T.120
      9. H.245
      10. H.324
      11. SUMMARY OF H.323
      12. MEDIA GATEWAY CONTROL PROTOCOL (MGCP)
      13. OTHER PROTOCOLS
      14. CALL AGENTS AND CALLS
      15. RELATIONSHIP TO H.323
      16. ENDPOINTS, CONNECTIONS, CALLS, EVENTS, PACKAGES, AND NAMES
      17. THE CONNECTION MODES
      18. MGCP COMMANDS: FOR THE API AND THE MESSAGES
      19. THE MGCP PARAMETERS
      20. API COMMANDS AND ASSOCIATED PARAMETERS
      21. MGCP MESSAGES AND ASSOCIATED PARAMETERS
      22. MESSAGES AND MESSAGE PARAMETERS
      23. EXAMPLES OF MGCP OPERATIONS
      24. SUMMARY
    12. Internetworking SS7 with IP and H.323
      1. WHY COMBINE IP AND SS7?
      2. POSSIBLE CONFIGURATIONS
      3. THE BASIC FRAMEWORK AND THE INTERNET SPECIFICATIONS
      4. TAKING ADVANTAGE OF SS7 CAPABILITIES
      5. THE SS7-IP ARCHITECTURAL FRAMEWORK
      6. THE RELIABLE SIGNALING GATEWAY PROTOCOL (RSGP)
      7. MESSAGES AND Q.931 MAPPINGS
      8. INTERWORKING H.323 AND SS7
      9. PROPOSAL FOR AN ADAPTATION LAYER
      10. SUMMARY
    13. Other VoIP Supporting Protocols
      1. IGMP and MBONE
      2. RSVP
      3. RTP
      4. RTCP
      5. NETWORK TIME PROTOCOL (NTP)
      6. SECURITY SERVICES
      7. DIAMETER
      8. IPDC
      9. DIFFSERV
      10. LABEL-SWAPPING PROTOCOLS
      11. SUMMARY
    14. Other Packet Voice Alternatives
      1. VOICE OVER FRAME RELAY (VoFR)
      2. SERVICE MULTIPLEXING
      3. VoFR
      4. VOICE OVER ATM (VoATM)
      5. VoFR AND VoATM: PARTNERS WITH OR COMPETITORS TO VoIP?
      6. LAYER-3 SWITCHING
      7. SUMMARY
    15. Telephony Signaling
      1. THE LOCAL LOOP
      2. THE OUTSIDE PLANT
      3. CONNECTING THE RESIDENCE
      4. TOLL OFFICES AND TRUNKS
      5. SUBSCRIBER SYSTEMS
      6. TELEPHONE SIGNALING BASICS
      7. ACCESS-LINE SIGNALING
      8. OTHER SIGNALING EXAMPLES
    16. ISDN and SS7
      1. PLACEMENT OF ISDN AND SS7
      2. ISDN SIGNALING MESSAGES
      3. MAJOR FUNCTIONS OF SS7
      4. THE SS7 TOPOLOGY
      5. THE SS7 LAYERS
      6. SS7 POINT CODES
      7. ISUP
      8. EXAMPLE OF ISDN AND SS7 SIGNALING
    17. Tutorial on the V.34 and V.90 Modems
      1. V.34
      2. V.90
    18. Abbreviations
      1. Abbreviations
        1. Glossary
    19. References