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Chapter 10 The Service Configuration Screens
User’s Guide
122
10.4.2 SIP Client Server
SIP is a client-server protocol. A SIP client is an application program or device that
sends SIP requests. A SIP server responds to the SIP requests.
When you use SIP to make a VoIP call, it originates at a client and terminates at a
server. A SIP client could be a computer or a SIP phone. One device can act as
both a SIP client and a SIP server.
10.4.3 SIP User Agent
A SIP user agent can make and receive VoIP telephone calls. This means that SIP
can be used for peer-to-peer communications even though it is a client-server
protocol. In the following figure, either A or B can act as a SIP user agent client to
initiate a call. A and B can also both act as a SIP user agent to receive the call.
Figure 48
SIP User Agent
10.4.4 SIP Proxy Server
A SIP proxy server receives requests from clients and forwards them to another
server.
In the following example, you want to use client device A to call someone who is
using client device C.
1
The client device (A in the figure) sends a call invitation to the SIP proxy server
(B).
A
B
Summary of Contents for MAX-207HW2
Page 7: ...Safety Warnings User s Guide 8...
Page 9: ...Contents Overview User s Guide 10...
Page 16: ...17 PART I Introduction and Wizards Getting Started 19 Introducing the Web Configurator 23...
Page 17: ...18...
Page 27: ...Chapter 2 Introducing the Web Configurator User s Guide 28...
Page 28: ...29 PART II Basic Screens The Main Screen 25 The Setup Screens 31...
Page 29: ...30...
Page 37: ...Chapter 3 The Setup Screens User s Guide 38...
Page 39: ...40...
Page 43: ...Chapter 4 The Status Screen User s Guide 44...
Page 57: ...Chapter 5 The LAN Configuration Screens User s Guide 58...
Page 75: ...Chapter 6 The WIFI Configuration Screen User s Guide 76...
Page 87: ...Chapter 7 The WAN Configuration Screens User s Guide 88...
Page 97: ...Chapter 8 The NAT Configuration Screens User s Guide 98...
Page 107: ...108...
Page 125: ...Chapter 10 The Service Configuration Screens User s Guide 126...
Page 141: ...Chapter 12 The Phone Book Screens User s Guide 142...
Page 143: ...144...
Page 147: ...Chapter 13 The Certificates Screens User s Guide 148...
Page 159: ...Chapter 14 The Remote Management Screens User s Guide 160...
Page 165: ...Chapter 16 The Status Screen User s Guide 166...
Page 166: ...167 PART VI Troubleshooting and Specifications Troubleshooting 169 Product Specifications 177...
Page 167: ...168...