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Chapter 9 Voice
P-2812HNU-51c User’s Guide
189
9.9.1 VoIP
VoIP is the sending of voice signals over Internet Protocol. This allows you to
make phone calls and send faxes over the Internet at a fraction of the cost of
using the traditional circuit-switched telephone network. You can also use servers
to run telephone service applications like PBX services and voice mail. Internet
Telephony Service Provider (ITSP) companies provide VoIP service.
Circuit-switched telephone networks require 64 kilobits per second (Kbps) in each
direction to handle a telephone call. VoIP can use advanced voice coding
techniques with compression to reduce the required bandwidth.
9.9.2 SIP
The Session Initiation Protocol (SIP) is an application-layer control (signaling)
protocol that handles the setting up, altering and tearing down of voice and
multimedia sessions over the Internet.
SIP signaling is separate from the media for which it handles sessions. The media
that is exchanged during the session can use a different path from that of the
signaling. SIP handles telephone calls and can interface with traditional circuit-
switched telephone networks.
SIP Identities
A SIP account uses an identity (sometimes referred to as a SIP address). A
complete SIP identity is called a SIP URI (Uniform Resource Identifier). A SIP
account's URI identifies the SIP account in a way similar to the way an e-mail
address identifies an e-mail account. The format of a SIP identity is SIP-
Number@SIP-Service-Domain.
SIP Number
The SIP number is the part of the SIP URI that comes before the “@” symbol. A
SIP number can use letters like in an e-mail address ([email protected] for
example) or numbers like a telephone number ([email protected]
for example).
SIP Service Domain
The SIP service domain of the VoIP service provider is the domain name in a SIP
URI. For example, if the SIP address is
, then
“VoIP-provider.com” is the SIP service domain.
Summary of Contents for P-2812HNU-51c
Page 2: ......
Page 8: ...Safety Warnings P 2812HNU 51c User s Guide 8 ...
Page 10: ...Contents Overview P 2812HNU 51c User s Guide 10 ...
Page 19: ...19 PART I User s Guide ...
Page 20: ...20 ...
Page 73: ...73 PART II Technical Reference ...
Page 74: ...74 ...
Page 88: ...Chapter 4 Status Screens P 2812HNU 51c User s Guide 88 ...
Page 118: ...Chapter 5 WAN Setup P 2812HNU 51c User s Guide 118 ...
Page 204: ...Chapter 9 Voice P 2812HNU 51c User s Guide 204 ...
Page 210: ...Chapter 10 File Sharing P 2812HNU 51c User s Guide 210 ...
Page 216: ...Chapter 11 Firewall P 2812HNU 51c User s Guide 216 ...
Page 223: ...Chapter 12 Certificate P 2812HNU 51c User s Guide 223 Figure 99 Certificate Details ...
Page 232: ...Chapter 13 Static Route P 2812HNU 51c User s Guide 232 ...
Page 236: ...Chapter 14 Policy Forwarding P 2812HNU 51c User s Guide 236 ...
Page 252: ...Chapter 16 Quality of Service QoS P 2812HNU 51c User s Guide 252 ...
Page 274: ...Chapter 19 Universal Plug and Play UPnP P 2812HNU 51c User s Guide 274 ...
Page 284: ...Chapter 21 Interface Group P 2812HNU 51c User s Guide 284 ...
Page 288: ...Chapter 22 System Settings P 2812HNU 51c User s Guide 288 ...
Page 292: ...Chapter 23 Logs P 2812HNU 51c User s Guide 292 ...
Page 300: ...Chapter 24 Tools P 2812HNU 51c User s Guide 300 ...
Page 320: ...Chapter 27 Product Specifications P 2812HNU 51c User s Guide 320 ...
Page 336: ...Appendix A Network Troubleshooting P 2812HNU 51c User s Guide 336 ...
Page 376: ...Appendix C Pop up Windows JavaScripts and Java Permissions P 2812HNU 51c User s Guide 376 ...
Page 388: ...Appendix D IP Addresses and Subnetting P 2812HNU 51c User s Guide 388 ...