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Chapter 11 Voice
P-2602HWLNI User’s Guide
175
5
User Agent 2
sends an OK response to
Proxy 2
after the call is answered. This is also
relayed back to
User Agent 1
via
Proxy 1
.
6
User Agent 1
and
User Agent 2
exchange RTP packets containing voice data directly,
without involving the proxies.
7
When
User Agent 2
hangs up, he sends a BYE request.
8
User Agent 1
replies with an OK response confirming receipt of the BYE request, and
the call is terminated.
11.2.7 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.
• G.729 is an Analysis-by-Synthesis (AbS) hybrid waveform codec that uses a filter based
on information about how the human vocal tract produces sounds. G.729 provides good
sound quality and reduces the required bandwidth to 8 kbps.
11.2.8 PSTN Call Setup Signaling
Dual-Tone MultiFrequency (DTMF) signaling uses pairs of frequencies (one lower frequency
and one higher frequency) to set up calls. It is also known as Touch Tone®. Each of the keys
on a DTMF telephone corresponds to a different pair of frequencies.
Pulse dialing sends a series of clicks to the local phone office in order to dial numbers.
4
11.2.9 MWI (Message Waiting Indication)
Enable Message Waiting Indication (MWI) enables your phone to give you a message–waiting
(beeping) dial tone when you have a voice message(s). Your VoIP service provider must have
a messaging system that sends message waiting status SIP packets as defined in RFC 3842.
4.
The ZyXEL Device does not support pulse dialing at the time of writing.
Содержание P-2602HWLNI
Страница 2: ......
Страница 7: ...Safety Warnings P 2602HWLNI User s Guide 7...
Страница 8: ...Safety Warnings P 2602HWLNI User s Guide 8...
Страница 24: ...Table of Contents P 2602HWLNI User s Guide 24...
Страница 32: ...List of Figures P 2602HWLNI User s Guide 32...
Страница 38: ...List of Tables P 2602HWLNI User s Guide 38...
Страница 39: ...39 PART I Introduction Introducing the ZyXEL Device 41 Introducing the Web Configurator 49...
Страница 40: ...40...
Страница 60: ...Chapter 2 Introducing the Web Configurator P 2602HWLNI User s Guide 60...
Страница 62: ...62...
Страница 86: ...Chapter 5 Bandwidth Management Wizard P 2602HWLNI User s Guide 86...
Страница 98: ...Chapter 6 Status Screens P 2602HWLNI User s Guide 98...
Страница 99: ...99 PART III Network WAN Setup 101 LAN Setup 117 Wireless LAN 129 Network Address Translation NAT Screens 155...
Страница 100: ...100...
Страница 154: ...Chapter 9 Wireless LAN P 2602HWLNI User s Guide 154...
Страница 166: ...Chapter 10 Network Address Translation NAT Screens P 2602HWLNI User s Guide 166...
Страница 167: ...167 PART IV VoIP Voice 169 VoIP Trunking 211 Phone Usage 227...
Страница 168: ...168...
Страница 226: ...Chapter 12 VoIP Trunking P 2602HWLNI User s Guide 226...
Страница 230: ...Chapter 13 Phone Usage P 2602HWLNI User s Guide 230...
Страница 232: ...232...
Страница 264: ...Chapter 15 Firewall Configuration P 2602HWLNI User s Guide 264...
Страница 268: ...Chapter 16 Content Filtering P 2602HWLNI User s Guide 268...
Страница 274: ...Chapter 17 Introduction to IPSec P 2602HWLNI User s Guide 274...
Страница 309: ...Chapter 19 Certificates P 2602HWLNI User s Guide 309 Figure 173 My Certificate Details...
Страница 320: ...Chapter 19 Certificates P 2602HWLNI User s Guide 320 Figure 181 Trusted Remote Host Details...
Страница 326: ...326...
Страница 330: ...Chapter 20 Static Route P 2602HWLNI User s Guide 330...
Страница 338: ...Chapter 21 Bandwidth Management P 2602HWLNI User s Guide 338...
Страница 342: ...Chapter 22 Dynamic DNS Setup P 2602HWLNI User s Guide 342...
Страница 360: ...Chapter 23 Remote Management Configuration P 2602HWLNI User s Guide 360...
Страница 372: ...Chapter 24 Universal Plug and Play UPnP P 2602HWLNI User s Guide 372...
Страница 374: ...374...
Страница 380: ...Chapter 25 System P 2602HWLNI User s Guide 380...
Страница 406: ...Chapter 28 Troubleshooting P 2602HWLNI User s Guide 406...
Страница 422: ...Chapter 30 Diagnostic P 2602HWLNI User s Guide 422...
Страница 432: ...Chapter 31 Product Specifications P 2602HWLNI User s Guide 432...
Страница 434: ...434...
Страница 446: ...Appendix A Setting up Your Computer s IP Address P 2602HWLNI User s Guide 446...
Страница 482: ...Appendix F Legal Information P 2602HWLNI User s Guide 482...
Страница 488: ...Appendix G Customer Support P 2602HWLNI User s Guide 488...