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Chapter 10 Voice
P-2802H(W)(L)-I Series User’s Guide
132
Figure 73
SIP Redirect Server
10.2.3.4 SIP Register Server
A SIP register server maintains a database of SIP identity-to-IP address (or domain name)
mapping. The register server checks your user name and password when you register.
10.2.4 RTP
When you make a VoIP call using SIP, the RTP (Real time Transport Protocol) is used to
handle voice data transfer. See RFC 1889 for details on RTP.
10.2.5 Pulse Code Modulation
Pulse Code Modulation (PCM) measures analog signal amplitudes at regular time intervals
and converts them into bits.
10.2.6 Voice Coding
A codec (coder/decoder) codes analog voice signals into digital signals and decodes the digital
signals back into analog voice signals. The ZyXEL Device supports the following codecs.
• G.711 is a Pulse Code Modulation (PCM) waveform codec. PCM measures analog signal
amplitudes at regular time intervals and converts them into digital samples. G.711 provides
very good sound quality but requires 64 kbps of bandwidth.
• G.726 is an Adaptive Differential PCM (ADPCM) waveform codec that uses a lower
bitrate than standard PCM conversion. ADPCM converts analog audio into digital signals
based on the difference between each audio sample and a prediction based on previous
samples. The more similar the audio sample is to the prediction, the less space needed to
describe it. G.726 operates at 16, 24, 32 or 40 kbps.
Summary of Contents for P-2802H-I Series
Page 1: ...www zyxel com P 2802H W L I Series VDSL VoIP IAD User s Guide Version 3 70 6 2007 Edition 1...
Page 2: ......
Page 7: ...Safety Warnings P 2802H W L I Series User s Guide 7...
Page 8: ...Safety Warnings P 2802H W L I Series User s Guide 8...
Page 10: ...Contents Overview P 2802H W L I Series User s Guide 10...
Page 32: ...List of Tables P 2802H W L I Series User s Guide 32...
Page 33: ...33 PART I Introduction Introducing the ZyXEL Device 35 Introducing the Web Configurator 43...
Page 34: ...34...
Page 50: ...Chapter 2 Introducing the Web Configurator P 2802H W L I Series User s Guide 50...
Page 51: ...51 PART II Wizard Internet and Wireless Setup Wizard 53 VoIP Wizard And Example 65...
Page 52: ...52...
Page 64: ...Chapter 3 Internet and Wireless Setup Wizard P 2802H W L I Series User s Guide 64...
Page 70: ...Chapter 4 VoIP Wizard And Example P 2802H W L I Series User s Guide 70...
Page 72: ...72...
Page 82: ...Chapter 5 Status Screens P 2802H W L I Series User s Guide 82...
Page 88: ...Chapter 6 WAN Setup P 2802H W L I Series User s Guide 88...
Page 116: ...Chapter 8 Wireless LAN P 2802H W L I Series User s Guide 116...
Page 154: ...Chapter 10 Voice P 2802H W L I Series User s Guide 154...
Page 174: ...Chapter 11 Firewalls P 2802H W L I Series User s Guide 174...
Page 178: ...Chapter 12 Content Filtering P 2802H W L I Series User s Guide 178...
Page 184: ...Chapter 13 Introduction to IPSec P 2802H W L I Series User s Guide 184...
Page 238: ...Chapter 16 Static Route P 2802H W L I Series User s Guide 238...
Page 250: ...Chapter 17 Quality of Service QoS P 2802H W L I Series User s Guide 250...
Page 254: ...Chapter 18 Dynamic DNS Setup P 2802H W L I Series User s Guide 254...
Page 282: ...Chapter 20 Universal Plug and Play UPnP P 2802H W L I Series User s Guide 282...
Page 284: ...284...
Page 324: ...Chapter 25 Troubleshooting P 2802H W L I Series User s Guide 324...
Page 334: ...Chapter 26 Product Specifications P 2802H W L I Series User s Guide 334...
Page 336: ...336...
Page 348: ...Appendix A Setting up Your Computer s IP Address P 2802H W L I Series User s Guide 348...
Page 404: ...Appendix G Legal Information P 2802H W L I Series User s Guide 404...
Page 410: ...Appendix H Customer Support P 2802H W L I Series User s Guide 410...