IP Media Server (Global Call)
Demo Guide
for Windows Operating Systems
November 2003
05-2065-002
Download from Www.Somanuals.com. All Manuals Search And Download.
Contents
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
About This Publication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Intended Audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Demo Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
System Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Preparing to Run the Demo. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Editing Configuration Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.1.1 File Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.1.2 Editing the IPMediaServer.cfg Configuration File . . . . . . . . . . . . . . . . . . . . . . . . . 15
Running the Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Using the Demo. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.3.1 Keyboard Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.3.2 Using the Media Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Demo Details. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Files Used by the Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.1.1 Demo Source Code Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.1.2 PDL Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.2.1 Module Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.2.2 EventRouter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.2.3 Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.2.4 Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Event Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
5.5.1 Event Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
5.5.2 Handling Keyboard Input Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.5.3 Handling SRL Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.5.4 Handling Application Exit Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.5.5 TSUsrEvent Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
IP Media Server (Global Call) Demo Guide – November 2003
3
Download from Www.Somanuals.com. All Manuals Search And Download.
Contents
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
4
IP Media Server (Global Call) Demo Guide – November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Contents
Figures
System Initialization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
IP Media Server (Global Call) Demo Guide – November 2003
5
Download from Www.Somanuals.com. All Manuals Search And Download.
Contents
Tables
Command Line Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Runtime Keyboard Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Files Used by the IP Media Server (Global Call) Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
PDL Files Used by the IP Media Server (Global Call) Demo . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Application Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
IP Module Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Voice Module Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
6
IP Media Server (Global Call) Demo Guide – November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Revision History
This revision history summarizes the changes made in each published version of this document.
Document No.
Publication Date
Description of Revisions
05-2065-002
November 2003
Fax not supported in SR 6.0 PCI Windows demo - removed all references
05-2065-001
September 2003
Initial version of document.
IP Media Server (Global Call) Demo Guide — November 2003
7
Download from Www.Somanuals.com. All Manuals Search And Download.
Revision History
8
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
About This Publication
This section describes the purpose of the guide, the intended audience, and provides references to
other documents that may be useful to the user.
• Purpose
Purpose
This guide provides information on the IP Media Server (Global Call) demo that is available with
your Intel® Dialogic® System Release 6.0 on PCI for Windows. The guide describes the demo, its
requirements, and provides details on how it works.
Intended Audience
This guide is intended for application developers who will be developing a media server
application using the Global Call API. Developers should be familiar with the C++ programming
language and the Windows* programming environment.
This information is intended for:
• Distributors
• Toolkit Developers
• Independent Software Vendors (ISVs)
• Value Added Resellers (VARs)
• Original Equipment Manufacturers (OEMs)
How to Use This Publication
Refer to this publication after you have installed the hardware and the system software.
This publication assumes that you are familiar with the Windows operating system and the C++
programming language.
The information in this guide is organized as follows:
IP Media Server (Global Call) Demo Guide — November 2003
9
Download from Www.Somanuals.com. All Manuals Search And Download.
About This Publication
demo
the demo
Related Information
See the following for more information:
• Intel® Dialogic® System Release 6.0 on PCI for Windows Release Guide
• Intel Dialogic and Intel NetStructure for DM3 Architecture for PCI on Windows Configuration
Guide
• Global Call IP Technology Guide
• Voice Software Reference: Programmer's Guide for Windows
• Voice Software Reference: Standard Runtime Library for Windows
10
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
1
1.
This chapter describes the basic features of the IP Media Server (Global Call) demo.
The IP Media Server (Global Call) demo is an object-oriented host-based application that
demonstrates using the Global Call API to build an IP media server, providing voice and fax
services via IP technology. The demo source code can be used as sample code for those who want
to begin developing an application from a working application.
The IP Media Server (Global Call) demo supports the following features:
• Voice service
• CSP barge in
• Configuration file
• Command line options
Note: The IP Media Server (Global Call) demo does not function as a gateway. Therefore, it can only
answer calls from the IP network. Gateway functionality can be added by writing additional
software code within the IP module that will allow it to make outgoing calls to the IP network, and
connecting a gateway to interface with the PSTN.
The IP Media Server (Global Call) demo is a cross-OS demo, designed to eventually run under
both the Windows and Linux environments. Most of the differences in the environments are
handled directly by the programming interface and are transparent to the user. Other differences,
due to inherent differences in the operating systems, are handled by the Platform Dependency
Library (PDL). For more information about the PDL refer to the source code in the pdl_win
directory.
IP Media Server (Global Call) Demo Guide — November 2003
11
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Description
12
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
2
2.
This chapter discusses the system requirements for running the IP Media Server (Global Call). It
contains the following topics:
• Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.1
2.2
Hardware Requirements
To run the IP Media Server (Global Call) demo, you need:
• Intel® NetStructure™ DM/IP Series board
• IP network cable
For other hardware requirements, such as memory requirements, see the Release Guide for the
system release you are using.
Software Requirements
To run the IP Media Server (Global Call) demo, you need the Intel® Dialogic® System Software
6.0 for Windows. For a list of operating system requirements see the Release Guide for the system
release you are using.
this demo. Using a non-supported compiler may cause unforeseen problems in running the demo.
IP Media Server (Global Call) Demo Guide — November 2003
13
Download from Www.Somanuals.com. All Manuals Search And Download.
System Requirements
14
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
3
3.
This chapter discusses the preparations necessary to run the IP Media Server (Global Call) demo. It
provides information about the following topics:
3.1
Editing Configuration Files
This section discusses how to configure the demo for your system. It contains the following topics:
3.1.1
3.1.2
File Location
Before running the IP Media Server (Global Call) demo, modify the IPMediaServer.cfg file to
reflect your system environment. Use a text editor and open the file from:
C:\Program Files\Dialogic\Demos\IPDemos\IPMediaServer\
Editing the IPMediaServer.cfg Configuration File
Below is an example of the IPMediaServer.cfg file. Update the following information:
ipProtocolName
The IP protocol for opening IP line devices. Values are: H323, SIP, both.
DTMFmode
Specifies how DTMF tones are transmitted. Possible values are: OutofBand (usually used with
low bandwith coders, e.g., GSM), InBand (usually used with G.711 coders), RFC2833.
Note: OutofBand is used for H.323 only.
Capability
Describes the transmit and receive coders. See the Global Call IP Technology Guide for
specific information about coder support. The parameters are as follows:
• TxType – The transmit voice coder
• TxFramesPerPkt – Specify the number of frames per packet for the selected Tx coder
• TxVAD – Specify if VAD is active for the selected Tx coder
• RxType – The receive voice coder
• RxFramesPerPkt – Specify the number of frames per packet for the selected Rx coder
• RxVAD – Specify if VAD is active for the selected Rx coder
Note: The G.711 coder defines frames per packet using the packet size in milliseconds, i.e. 10, 20, or 30
IP Media Server (Global Call) Demo Guide — November 2003
15
Download from Www.Somanuals.com. All Manuals Search And Download.
Preparing to Run the Demo
Quality of Service
The application can set threshold values to monitor the quality of service during calls. A fault
occurs when the result of a measurement of a QoS parameter crossed a predefined threshold. A
success occurs when the result of a measurement of a QoS parameter did not cross a
predefined threshold. The QoS parameters are measured during time intervals, starting when a
call is established. The following parameters are supported:
• MediaAlarmLostPackets – monitors the number of lost IP packets during a call
• MediaAlarmJitter – monitors the jitter (as defined in RFC 1889) during IP transmission
QoS Attributes
The threshold for each QoS parameter is measured with the following six attributes:
• Threshold – defines when a QoS parameter is in a fault condition. A fault occurs when the
result of a measurement of a QoS parameter crossed the Threshold value.
• DebounceOn – the time during which faults are measured (in msec., must be multiple of
Interval)
• DebounceOff – the time during which successes are measured (in msec., must be multiple
of Interval)
• Interval – the amount of time between two QoS parameter measurements (in multiples of
100 msec)
• Percent_Fail – used to detect failure condition, together with DebounceOn (expressed as
a percentage of failures)
• Percent_Success – used to detect failure recovery, together with DebounceOff (expressed
as a percentage of successes)
The default values are as follows:
Percent_
Fail
Percent_
Success
Threshold DebounceOn DebounceOff
Interval
Lost packets
Jitter
20
60
10000
20000
10000
60000
1000
5000
60
60
40
40
Sample Configuration File
################################################################################################
# IP Protocol :
#
#
The IP Protocol used for opening the IP Line devices, values: H323, SIP, both
# DTMFmode
#possible options:
#OutOfBand, inband, rfc2833
#
# Capability posiblities:
#
#
#
#
#
#
#
#
#
#
#
#
#
#
g711Alaw
g711Mulaw
gsm
gsmEFR
g723_5_3k
g723_6_3k
g729a
g729ab
t38UDPFax
Note: if you want to run the demo with coder g729 use:
g729a for running with VAD disable
and 729ab for running with VAD enable
# Caution:
16
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Preparing to Run the Demo
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
If capability is g711Alaw /Mulaw ==> FramesPerPkt = 10,20,30.
G711 frame per packet defines the packet size in
milliseconds
If capability is g723_5_3k / 6_3k ==> FramesPerPkt = 1, 2, 3 .
FrameSize isn't needed, default= 30ms.
==> FramesPerPkt = 1, 2, 3 .
FrameSize isn't needed, default= 20ms.
==> FramesPerPkt = 1, 2, 3 .
FrameSize isn't needed, default= 20ms.
==> FramesPerPkt = 3, 4 .
If capability is gsm
If capability is gsmEFR
If capability is g729a
FrameSize isn't needed, default= 10ms.
VAD disable, the VAD parameter is ignored
==>FramesPerPkt = 3, 4 .
If capability is g729ab
FrameSize isn't needed, default= 10ms.
VAD enable, the VAD parameter is ignored
################################################################################################
ipProtocolName = H323
DTMFmode = inBand
Channel = 1-120
{
Capability
{
TxType = g711Mulaw
TxFramesPerPkt = 30
TxVAD = 0
RxType = g711Mulaw
RxFramesPerPkt = 30
RxVAD = 0
}
MediaAlarmLostPackets
{
Threshold
DebounceOn
DebounceOff
Interval
= 20
# Threshold value
= 10000 # Threshold debounce ON
= 10000 # Threshold debounce OFF
= 1000 # Threshold Time Interval (ms)
PercentSuccess = 60
PercentFail = 40
# Threshold Success Percent
# Threshold Fail Percent
}
MediaAlarmJitter
{
Threshold
DebounceOn
DebounceOff
Interval
= 60
# Threshold value
= 20000 # Threshold debounce ON
= 60000 # Threshold debounce OFF
= 5000 # Threshold Time Interval (ms)
PercentSuccess
PercentFail
}
= 60
= 40
# Threshold Success Percent
# Threshold Fail Percent
# MediaAlarmResetAlarmState
}
= 0
3.2
Compiling and Linking
Compile the project within the following environments:
• Microsoft Visual Studio® 6.0 with Service Pack 5
If you have added or changed files, to compile the project put the files in C:\Program
Files\Dialogic\Demos\IPDemos\IPMediaServer.
IP Media Server (Global Call) Demo Guide — November 2003
17
Download from Www.Somanuals.com. All Manuals Search And Download.
Preparing to Run the Demo
Set IpMediaServer as the active project and build in debug mode.
18
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
4
4.
unning the Demo
This chapter discusses how to run the IP Media Server (Global Call) demo. It contains the
following topics:
• Using the Demo. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
• Stopping the Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.1
4.2
Starting the Demo
Select Run from the Start Menu. The demo executable file can be found in: C:\Program
Files\Dialogic\Demos\IPDemos\IPMediaServer\Release\IPMediaServer.exe. Click OK to run the
IP Media Server (Global Call) demo using the default settings.
Demo Options
To specify certain options at run-time, launch the demo from a command line, using any of the
Table 1. Command Line Switches
Switch
Action
Configuration file name
Sets the encoding type:
Default
-cIPMediaServer.cfg
-em
-c<filename>
-e<encoding
type>
•
•
m – muLaw
a – A-Law
-h or ?
Prints the command syntax to the screen
Sets the number of channels
Off
-n<n>
The lesser of Voice
Devices or IP
devices
-q
Activates Quality of Service
Disabled
Example
The following example shows how to launch the demo from a command line with options:
IPMediaServer -n64 -cmyconfig.cfg -ea
This command launches the demo with 64 channels, using the myconfig.cfg configuration file and
A-Law encoding.
IP Media Server (Global Call) Demo Guide — November 2003
19
Download from Www.Somanuals.com. All Manuals Search And Download.
Running the Demo
4.3
Using the Demo
This section describes how to use the IP Media Server (Global Call) demo and contains the
following topics:
4.3.1
Keyboard Commands
The demo always waits for input from the keyboard. While the demo is running, you may enter any
Table 2. Runtime Keyboard Commands
Command
Function
q or Q or Ctrl+c
Terminates the application
4.3.2
Using the Media Server
The IP Media Server (Global Call) demo allows the caller to interact with a series of voice menus,
using the telephone keypad to enter an option. Basic operations include playing a pre-recorded
message, recording a new message, and barge-in for CSP. Each menu prompts the caller to select
an action by pushing a key. The call state within which the menu is called is indicated by the square
Main Menu [Main_Menu]
1 - Voice Mail
4 - CSP
* - Quit
Voice Mail Menu [Voicemail_Menu]
1 - Record Message
2 - Listen to message from a mailbox
* - Quit
Send Message Prompt [SendMsg_Menu]
Enter Mailbox Number - between 101 - 299
* - Quit
20
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Running the Demo
Start Record Prompt [Record_Menu]
2 - Start Record
Press 2 at end of message to stop recording (at end Stop Record Prompt is played)
* - Quit
Stop Record Prompt [StopRec_Menu]
2 - Discard Message and re-record message to same mailbox
3 - Confirm Message [Save_Confirm]
4 - Listen to Message (and replay Stop Record Prompt)
* - Quit without saving
Confirm Message Saved [StopRec_Menu]
1 - Record a message
2 - Listen to a message from a mailbox
* - Quit
Listen to Message Prompt [ListenMsg_Menu]
Enter Mailbox Number - between 101 - 299 (Recorded message is played)
* - Quit
Stop Listen Prompt [Listening]
2 - Discard message and quit
* - Save message and quit
CSP Prompt [CSP_Menu]
Say something to barge in (new file will be created with barged in message)
* - Quit
IP Media Server (Global Call) Demo Guide — November 2003
21
Download from Www.Somanuals.com. All Manuals Search And Download.
Running the Demo
Figure 1. Demo Voice Menu Flowchart
Main Menu
Select one of the following:
1 - Voice Mail
4 - CSP
* - Quit
4
1
2
-
Fax
Voice Mail Prompt
1 - Record Message
2 - Listen to message
from a mailbox
CSP Prompt
Say something to barge in
* - Quit
* - Quit
2
1
Listen Message
Prompt
Enter Mailbox
Number (Message
is played)
Send Message
Prompt
Enter Mailbox
Number
* - Quit
* - Quit
Mailbox
number
Mailbox
number
Stop Listen Prompt
2 - Discard message
and quit
* - Save message and
quit
Start Record Prompt
2 - Start/Stop Record
* - Quit
2
2
Stop Record Prompt
2 - Discard message and
re-record message to
same mailbox
3 - Confirm message
4 - Replay message
* - Quit
3
4
Confirm Message Saved
Prompt
Confirm message
Replay Message
Replay Stop Record
Prompt
Return to Voice Mail prompt
22
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Running the Demo
24
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
5
5.
This chapter discusses the IP Media Server (Global Call) demo in more detail. It contains the
following topics:
• Threads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.1
Files Used by the Demo
This section lists the files used by the IP Media Server (Global Call) demo. It contains the
following information
5.1.1
Demo Source Code Files
C:\Program Files\Dialogic\Demos\IPDemo\
Table 3. Files Used by the IP Media Server (Global Call) Demo
Directory
IPMediaServer
File Name
CConfig.cpp
Purpose
Implements the operations of the Configuration
class
IPMediaServer
CConfig.h
Function prototype for config.cpp
IPMediaServer
CEventRouter.cpp
CEventRouter.h
IPMediaServer.cfg
IPMediaServer.dsp
IPMediaServer.dsw
main.cpp
Implements the operations of the EventRouter class
Function prototype for ceventrouter.cpp
Demo configuration file
IPMediaServer
IPMediaServer
IPMediaServer
Visual C++ project file
IPMediaServer
Visual C++ project workspace
Contains the main function and the WaitForKey
Function prototype for main.cpp
Voice file
IPMediaServer
IPMediaServer
main.h
IPMediaServer\release
IPMediaServer\Release
unavConf.vox
cspPrompt.vox
Voice file
IP Media Server (Global Call) Demo Guide — November 2003
25
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 3. Files Used by the IP Media Server (Global Call) Demo (Continued)
Directory
File Name
errorInput.vox
Purpose
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
IPMediaServer\Release
Modules\common
Voice file
IPMediaServer.cfg
IPMediaServer.exe
listenMenu.vox
mainMenu.vox
savecCnfirm.vox
sendfaxMenu.vox
sendMsg.vox
Demo configuration file
Demo executable
Voice file
Voice file
Voice file
Voice file
Voice file
startRec.vox
Voice file
stopListen.vox
stopRec.vox
Voice file
Voice file
thankYou.vox
Voice file
unavCsp.vox
Voice file
unavFax.vox
Voice file
unavMenu.vox
voicemailMenu.vox
Defines.h
Voice file
Voice file
Definitions and structures for the demo
Interfaces used in the demo
Parameters used in the demo
Implements the operations of the CIPDevice class
Function prototype for cipdevice.cpp
Implements the operations of the CIPMBoard class
Function prototype for cipmboard.cpp
Implements the operations of the CIPModule class
Function prototype for cipmodule.cpp
Modules\common
Interfaces.h
Modules\common
Parameters.h
CIPDevice.cpp
CIPDevice.h
Modules\IPModule
Modules\IPModule
Modules\IPModule
CIPMBoard.cpp
CIPMBoard.h
CIPModule.cpp
CIPModule.h
Modules\IPModule
Modules\IPModule
Modules\IPModule
Modules\IPModule
CIPStateMachine.cpp
Implements the operations of the CIPStateMachine
class
Modules\IPModule
Modules\IPModule
Modules\IPModule
Modules\IPModule
CIPStateMachine.h
CIPTBoard.cpp
CIPTBoard.h
Function prototype for cipstatemachine.cpp
Implements the operations of the CIPTBoard class
Function prototype for ciptboard.cpp
CMediaAlarms.cpp
Implements the operations of the CMediaAlarms
class
Modules\IPModule
Modules\IPModule
CMediaAlarms.h
IPModule.dsp
IPModule.lib
Function prototype for cmediaalarms.cpp
Visual C++ project file
Modules\IPModule\
Release
Compiled IP Module library
26
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 3. Files Used by the IP Media Server (Global Call) Demo (Continued)
Directory
Modules\
File Name
Purpose
CCSPDevice.cpp
Implements the operations of the CCSPDevice class
VoiceModule
Modules\
CCSPDevice.h
Function prototype for ccdspdevice.cpp
VoiceModule
Modules\
VoiceModule
CMailBoxBtil.cpp
CMailBoxUtil.h
Implements the operations of the CMailBoxUtil class
Function prototype for cmailboxutil.cpp
Modules\
VoiceModule
Modules\
VoiceModule
CVoiceBoard.cpp
CVoiceBoard.h
CVoiceDevice.cpp
CVoiceDevice.h
CVoiceModule.cpp
CVoiceModule.h
Implements the operations of the voiceBoard class
Function prototype for cvoiceboard.cpp
Modules\
VoiceModule
Modules\
VoiceModule
Implements the operations of the CVoiceDevice
class
Modules\
VoiceModule
Function prototype for cvoicedevice.cpp
Modules\
VoiceModule
Implements the operations of the CVoiceModule
class
Modules\
Function prototype for cvoicemodule.cpp
VoiceModule
Modules\
VoiceModule
CVoiceStateMachine.cpp Implements the operations of the
CVoiceStateMachine class
Modules\
VoiceModule
CVoiceStateMachine.h
VoiceModule.dsp
VoiceModule.lib
Function prototype for cvoicestatemachine.cpp
Modules\
VoiceModule
Visual C++ project file
Modules\
Compiled Voice Module library
VoiceModule\Release
5.1.2
PDL Files
C:\Program Files\Dialogic\Demos\IPDemo\Shared\
Table 4. PDL Files Used by the IP Media Server (Global Call) Demo
Directory
pdl_win
File Name
iptransport.cpp
iptransport.h
pdl.c
Purpose
PDL IP transport functions
pdl_win
pdl_win
pdl_win
pdl_win
Function prototype for iptransport.cpp
Platform dependency functions
Function prototype for pdl.c
PDL version information
pdl.h
pdl.ver
IP Media Server (Global Call) Demo Guide — November 2003
27
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 4. PDL Files Used by the IP Media Server (Global Call) Demo (Continued)
Directory
pdl_win
File Name
pdl_win.dsp
Purpose
PDL Visual C project file
pdl_win
pdl_win.dsw
psl_win.lib
PDL Visual C project workspace
Compiled PDL library
pdl_win\release
5.2
Programming Model
This section describes the IP Media Server (Global Call) demo architecture. It contains the
following topics:
• Classes
5.2.1
Module Structure
The IP Media Server (Global Call) demo uses a modular architecture, in which each technology
(IP, voice, CSP) is wrapped inside a module so that a particular technology can be easily added or
removed.
The system contains two modules:
• IP module that serves as the front end to communicate with the IP network
• Voice module to provide voice service
The system also contains a software component, the EventRouter, to connect the modules. The
28
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Figure 2. IP Media Server (Global Call) Demo Architecture
Voice Module
Board
Device
State Machine
IP Module
Board
Device
EventRouter
State Machine
User Module
Board
Device
State Machine
Each module is composed of four elements:
• Board
• Device
• State Machine (call control)
• Wrapper
The Wrapper acts like a manager, receiving requests from the EventRouter and distributing the
request to the boards or devices. A device can have one or multiple state machines attached to it.
Each state machine represents one call.
5.2.2
EventRouter
The EventRouter is responsible for communicating with the modules. It does the following:
• Maintains routing tables
• Retrieves event data from the SRL and routes it to a module for processing
• Forwards event process result to another module if so requested.
IP Media Server (Global Call) Demo Guide — November 2003
29
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Figure 3. EventRouter
Retrieve event
data from GC
library
Forward result to destination
For which
technology?
I P
Voice
Voice Module
IP Module
Yes
result
result
No
result.destination
= NONE ?
5.2.3
Interfaces
The modular architecture implements a unified interface that allows replacement of modules by
including new header files and adjusting routing statements.
30
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
A module is treated by the EventRouter as a block box. It has three types of APIs:
Initialization
• Init( ) – for initializing a module
• GetNumOfDevices( ) – returns the number of devices available to the application
• GetDeviceHandle( ) – returns a device handle
• GetDeviceXmitSlot( ) – returns a device transmit timeslot
• SetDeviceReceiveSlot( ) – sets a device receive timeslot
Runtime
• ProcessEvent( ) – processes event data
Termination
• Exit( ) – exits a module
5.2.4
Classes
This section describes the classes contained in the demo and within each module. Each module
contains three classes: board, device, and state machine.
Table 5. Application Classes
Class Name
Interface
CConfig
ParseConfigFile( )
• Responsible for parsing configuration file and
• Parses configuration file
populating configuration variables in the program.
ChannelNumber( )
• Gets the number of channels that are the
minimum of the number of voice lines and the
number of IP lines
IPParms( )
• Returns configured IP parameters
VoiceParms( )
• Returns configured voice parameters
CEventRouter
Init( )
Responsible for connecting all the modules. It does
the following:
• Initializes the IP module, voice module, and fax
module
• Maintains routing tables
• Builds event routing tables
• Retrieves event data from the SRL and routes
them to modules
Exit( )
• Terminates IP module, voice module, and fax
module
• Gets event process results from the modules and
routes them to other modules if the destination is
not NONE
ProcessEvent( )
• Retrieves event data from Global Call and routes
them to a module for processing
• Routes processing result to other module(s) for
further processing.
IP Media Server (Global Call) Demo Guide — November 2003
31
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 6. IP Module Classes
Category
Module
Class Name
Interface
CIPModule
Init( )
• Interacts with CIPBoard and CIPDevice.
• Starts host based IP protocol
• Exports IP module functions to
• Creates and initializes IPT (virtual) board
CEventRouter.
objects
Note: The public functions in this class can
be accessed by classes outside the
IP module.
• Creates and initializes IPM (media) board
objects
• Creates and initializes IP device objects
Exit( )
• Terminates and closes IPT boards
• Terminates and closes IPM boards
• Terminates and closes IP devices
ProcessEvent( )
• Receives event data from the event
router and distributes them, based on
handles, to IPT boards, IPM boards or IP
devices
GetNumOfDevices( )
• Returns number of IP devices engaging
in the communication
GetDeviceHandle( )
• Returns an IP device handle
GetDeviceXmitSlot( )
• Returns the transmit timeslot of an IP
device
SetDeviceReceiveSlot( )
• Sets the receiving timeslot of an IP
device
32
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 6. IP Module Classes (Continued)
Category
Board
Class Name
Interface
CIPTBoard
Init( )
• Interacts with the Global Call library to
• Opens IPT (virtual) board and sets board
handle IP virtual boards
parameters
Note: The public function in this class
should only be accessed by classes
inside the IP module.
Exit( )
• Closes IPT (virtual) Board
ProcessEvent( )
• Processes IPT (virtual) board events
GetNumOfDevicesOnBoard( )
• Returns the number of IPT devices
(signaling devices) on the board
CIPMBoard
Init( )
• Interacts with the Global Call library to
• Opens IP media boards
handle IP media boards
Exit( )
Note: The public functions in this class
should only be accessed by classes
inside the IP module.
• Closes IP media boards
ProcessEvent( )
• Processes IP media board events
GetNumOfDevices( )
• Returns number of IPM devices on the
board
IP Media Server (Global Call) Demo Guide — November 2003
33
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 6. IP Module Classes (Continued)
Category
Device
Class Name
Interface
CIPDevice
Init( )
• Handles IP device operations, such as
making/dropping calls, sending H.323
messages, making timeslot connections,
etc.
• Opens an IP device. If successful,
creates an IP state machine. If QoS is
enabled, creates a media alarm object.
Exit( )
• Holds CIPStateMachine (or call control)
• Deletes IP state machine
• Deletes media alarm object
• Closes IP devices
Note: The public functions in this class
should only be accessed by classes
inside the IP module.
ProcessEvent( )
• Processes IP device events
Connect( )
• Allows IP device to listen to its receiving
timeslot
Disconnect( )
• Allows IP device to unlisten to its
receiving timeslot
GetDeviceHandle( )
• Returns IP device handle
GetXmitSlot( )
• Returns IP device transmit timeslot
SetDeviceReceiveSlot( )
• Sets IP device receiving timeslot
SetFaxHandle( )
• Sets fax device handle associated with
the device
GetFaxHandle( )
• Returns fax device handle associated
with the device
State Machine CIPStateMachine
• Handles IP events and maintains IP state
Init( )
• Initializes the IP state machine
machine(s)
Exit( )
Note: The public functions in this class
should only be accessed by the
classes inside the IP module.
• Terminates the IP state machine
ProcessEvent( )
• Processes IP call events
34
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 7. Voice Module Classes
Category
Class Name
Interface
Module
CVoiceModule
Init( )
• Interacts with CVoiceBoard and
CVoiceDevice.
• Opens and initializes voice board objects
• Opens and initializes voice device objects
• Exports Voice module functions to
CEventRouter.
Exit( )
• Terminates and closes voice boards
• Terminates and closes voice devices
Note: The public functions in this class can
be accessed by classes outside the
Voice module.
ProcessEvent( )
• Receives event data from the event
router and distributes them, based on
devicehandles, to voice boards or voice
devices for processing
Board
CVoiceBoard
Init( )
• Interacts with the voice library to handle
• Opens voice board
voice boards
Exit( )
Note: The public function in this class
should only be accessed by classes
inside the Voice module.
• Closes voice board
ProcessEvent( )
• Processes voice board events
IP Media Server (Global Call) Demo Guide — November 2003
35
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 7. Voice Module Classes (Continued)
Category
Device
Class Name
Interface
CVoiceDevice
Init( )
• Handles voice device operations, such as
playing, recording, tone detection, and
tone generation
• Opens the voice device. If successful,
creates voice state machine.
Exit( )
• Holds CVoiceStateMachine
• Deletes the voice state machine from the
voice device
Note: The public functions in this class
should only be accessed by classes
inside the Voice module.
• Closes voice device
ProcessEvent( )
• Processes voice device events
Connect( )
• Allows IP device to listen to its receiving
timeslot
Play( )
• Plays a vox file
OnPlayComplete( )
• Replays a vox file when it has finished
playing
Record( )
• Records voice to a vox file
GetDigits( )
• Retrieves DTMF digits
GetDigitCount( )
• Returns the number of retrieved DTMF
digits
GetDigitString( )
• Returns retrieved DTMF string
Connect( )
• Allows the voice device to listen to its
receiving timeslot
Disconnect( )
• Allows voice device to unlisten to its
receiving timeslot
GetStoppedReason( )
• Tells why a played voice file stops
GetDeviceHandle( )
• Returns voice device handle
GetXmitSlot( )
• Returns voice device transmit timeslot
SetReceiveSlot( )
• Sets voice device receiving timeslot
36
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Table 7. Voice Module Classes (Continued)
Category
Class Name
Interface
State Machine CVoiceStateMachine
Init( )
• Opens vox files
• Handles voice events and maintains
voice state machine(s)
• Creates mailbox utility object that
Note: The public functions in this class
should only be accessed by the
classes inside the voice module.
manages mailboxes
Exit( )
• Closes vox files
• Deletes mailbox utility object that
manages mailboxes
ProcessEvent( )
• Processes voice events
Misc
CMailBoxUtil
InitMailBoxes( )
• Provides utility function to manage
• Initializes mailboxes
mailboxes
CheckAndConvertDigits( )
Note: The public functions in this class
should only be accessed by the
classes inside the voice module
• Checks if the extension number is in
allowed range. If it is, converts it into an
integer.
GetMailBox( )
• Checks if the mailbox is ready to be used.
If it is, gets the mailbox.
CreateMailBoxFileName( )
• Creates a filename for the mailbox
FreeMailBox( )
• Frees the mailbox for future use
5.3
Threads
The IP Media Server (Global Call) demo operates with two threads, as shown in Figure 4.
Figure 4. IP Media Server (Global Call) Demo Threads
IP
R4/GC
Keyboard
SRL
Main Thread
Sub-Thread
IP Media Server (Global Call) Demo Guide — November 2003
37
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
The threads are created as follows:
1. The first (main) thread is created by the demo application to get the keyboard input.
2. The second thread is an SRL thread, created as a result of the demo application calling
PDLsr_enblhdlr( ). All Global Call events are received through the SRL.
5.4
Initialization
A system is started in the following sequence:
1. The application creates CConfig( ) to parse the configuration file.
2. The application creates CEventRouter( ) to start the Event Router, which, in turn, starts the IP
module and the Voice module. When a module is started, it initializes its boards, devices and
state machines.
After all the modules are started, the EventRouter starts to build a static routing table that maps
voice devices to IP devices. It is important that each IP device has a dedicated voice resource, so
that when an IP channel is connected (an incoming call is answered) the user can get a voice
prompt immediately.
If the initialization should fails, the application shuts down. The shutdown sequence is the reverse
of the initialization sequence.
38
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
Figure 5. System Initialization
1. Parse .cfg file
Application
Configuration
Event Router
2. Start router
3. Start IP Module
4. Start IP Board
5. Start IP Device
IP Module
IP Board
IP Device
6. Start IP State Machine
IP State Machine
7. Start Voice Module
8. Start Voice Board
Voice Module
Voice Board
9. Start VoiceDevice
Voice Device
10. Start Voice State
Machine
Voice State
Machine
5.5
Event Handling
This section describes how the IP Media Server (Global Call) demo handles events. It contains the
following topics:
5.5.1
Event Mechanism
The IP Media Server (Global Call) demo uses the SRL mechanism to retrieve events. When an
event occurs, SRL calls event handlers automatically. All events are received by the SRL and then
passed to the CallbackHdlr( ) function for handling.
In the initialization phase of the demo, the main( ) function sets up the call-back handler, by calling
PDLsr_enbhdlr( ).
IP Media Server (Global Call) Demo Guide — November 2003
39
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
5.5.2
Handling Keyboard Input Events
There is an endless loop {while(0)} in the main( ) function in the Main.cpp file. In that loop, the
application waits forever for a keyboard event by calling the waitForKey( ) function. The event
must be handled immediately and event-specific information should be retrieved before the next
call to waitForKey( ).
5.5.3
Handling SRL Events
When the R4/Global Call event is received, the application performs the following:
1. Get METAEVENT by calling gc_GetMetaEvent( ).
2. Get channel ID through device handle to channel mapping.
3. Get device type through device handle to type mapping.
4. Route meta event to the module specified by device type.
5.5.4
5.5.5
Handling Application Exit Events
Normal application exit events, such as pressing either q or Q, or Ctrl+C, don’t enter the SRL. The
main( ) function calls PDLSetApplicationExitPath( ) before initialization. In Windows, this
function enables the detection of CTRL_CLOSE_EVENT (closing the window).
TSUsrEvent Structure
The TSUsrEvent structure is used by the demo modules to return event processing results to the
event router. It has five fields:
Event
The name of a user defined event, such as USR_CONNECTED, etc.
Destination
The name of the module that this event is destined for. A destination can be IP, VOICE, or
NONE.
lineDevice
The device handle in this module. It will be later used by the Event Router as an index to find
its counterpart in the destination module.
xmitSlot
An integer normally to be filled with with a time slot
neighborDevice
neighbor device handle
dialString
A char string normally to be filled with a DTMF dialing string.
The TSUserEvt structure is defined as follows:
40
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
typedef struct
{
int
event;
TDeviceType destination;
int
lineDevice;
long
xmitSlot;
long
char
neighborDevice;
dialString[MAX_STRING_LENGTH]}
TSUserEvent;
IP Media Server (Global Call) Demo Guide — November 2003
41
Download from Www.Somanuals.com. All Manuals Search And Download.
Demo Details
42
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
Glossary
Codec: see COder/DECoder
COder/DECoder: A circuit used on Dialogic boards to convert analog voice data to digital and digital voice data
to analog audio.
Computer Telephony (CT): Adding computer intelligence to the making, receiving, and managing of
telephone calls.
DTMF: See Dual-Tone Multi-Frequency
Dual-Tone Multi-Frequency: A way of signaling consisting of a push-button or touch-tone dial that sends out a
sound consisting of two discrete tones that are picked up and interpreted by telephone switches (either PBXs or
central offices).
Emitting Gateway: called by a G3FE. It initiates IFT service for the calling G3FE and connects to a Receiving
Gateway.
E1: The 2.048 Mbps digital carrier system common in Europe.
FCD file: An ASCII file that lists any non-default parameter settings that are necessary to configure a DM3
hardware/firmware product for a particular feature set. The downloader utility reads this file, and for each
parameter listed generates and sends the DM3 message necessary to set that parameter value.
Frame: A set of SCbus/CT bus timeslots which are grouped together for synchronization purposes. The period of
a frame is fixed (at 125 µsec) so that the number of time slots per frame depends on the SCbus/CT bus data rate. In
the context of DSP programming (e.g. DM3 component development), the period defined by the sample rate of the
signal data.
G3FE: Group 3 Fax Equipment. A traditional fax machine with analog PSTN interface.
Gatekeeper: An H.323 entity on the Internet that provides address translation and control access to the network
for H.323 Terminals and Gateways. The Gatekeeper may also provide other services to the H.323 terminals and
Gateways, such as bandwidth management and locating Gateways.
Gateway: A device that converts data into the IP protocol. It often refers to a voice-to-IP device that converts an
analog voice stream, or a digitized version of the voice, into IP packets.
H.323: A set of International Telecommunication Union (ITU) standards that define a framework for the
transmission of real-time voice communications through Internet protocol (IP)-based packet-switched networks.
The H.323 standards define a gateway and a gatekeeper for customers who need their existing IP networks to
support voice communications.
IAF: Internet Aware Fax. The combination of a G3FE and a T.38 gateway.
IFP: Internet Facsimile Protocol
IP Media Server (Global Call) Demo Guide — November 2003
43
Download from Www.Somanuals.com. All Manuals Search And Download.
IFT: Internet Facsimile Transfer
International Telecommunications Union (ITU): An organization established by the United Nations to set
telecommunications standards, allocate frequencies to various uses, and hold trade shows every four years.
Internet: An inter-network of networks interconnected by bridges or routers. LANs described in H.323 may be
considered part of such inter-networks.
Internet Protocol (IP): The network layer protocol of the transmission control protocol/Internet protocol
(TCP/IP) suite. Defined in STD 5, Request for Comments (RFC) 791. It is a connectionless, best-effort packet
switching protocol.
Internet Service Provider (ISP): A vendor who provides direct access to the Internet.
Internet Telephony: The transmission of voice over an Internet Protocol (IP) network. Also called Voice over IP
(VoIP), IP telephony enables users to make telephone calls over the Internet, intranets, or private Local Area
Networks (LANs) and Wide Area Networks (WANs) that use the Transmission Control Protocol/Internet Protocol
(TCP/IP).
ITU: See International Telecommunications Union.
Jitter: The deviation of a transmission signal in time or phase. It can introduce errors and loss of synchronization
in high-speed synchronous communications.
NIC (Network Interface Card): Adapter card inserted into computer that contains necessary software and
electronics to enable a station to communicate over network.
PCD file: An ASCII text file that contains product or platform configuration description information that is used
by the DM3 downloader utility program. Each of these files identifies the hardware configuration and firmware
modules that make up a specific hardware/firmware product. Each type of DM3-based product used in a system
requires a product-specific PCD file.
PSTN: see Public Switched Telephone Network
Public Switched Telephone Network: The telecommunications network commonly accessed by standard
telephones, key systems, Private Branch Exchange (PBX) trunks and data equipment.
Reliable Channel: A transport connection used for reliable transmission of an information stream from its
source to one or more destinations.
Reliable Transmission: Transmission of messages from a sender to a receiver using connection-mode data
transmission. The transmission service guarantees sequenced, error-free, flow-controlled transmission of messages
to the receiver for the duration of the transport connection.
RTCP: Real Time Control Protocol
RTP: Real Time Protocol
SCbus: The standard bus for communication within a SCSA node. The architecture of the SCbus includes a 16-
wire TDM data bus that operates at 2, 4 or 8 Mbps and a serial message bus for control and signaling. DM3
44
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
platforms provide an SCbus interface for interconnection of multiple DM3 platforms, or connection to other SCSA-
compatible hardware. The DM3 platform supports timeslot bundling for high bandwidth, and can access up to 256
of the 2048 SCbus timeslots via two SC4000 ASICs.
SIP: Session Initiation Protocol: an Internet standard specified by the Internet Engineering Task Force (IETF) in
RFC 2543. SIP is used to initiate, manage, and terminate interactive sessions between one or more users on the
Internet.
T1: A digital transmission link with a capacity of 1.544 Mbps used in North America. Typically channeled into 24
digital subscriber level zeros (DS0s), each capable of carrying a single voice conversation or data stream. T1 uses
two pairs of twisted pair wires.
TCP: see Transmission Control Protocol
Terminal: An H.323 Terminal is an endpoint on the local area network which provides for real-time, two-way
communications with another H.323 terminal, Gateway, or Multipoint Control Unit. This communication consists
of control, indications, audio, moving color video pictures, and/or data between the two terminals. A terminal may
provide speech only, speech and data, speech and video, or speech, data, and video.
Transmission Control Protocol: The TCP/IP standard transport level protocol that provides the reliable, full
duplex, stream service on which many application protocols depend. TCP allows a process on one machine to send
a stream of data to a process on another. It is connection-oriented in the sense that before transmitting data,
participants must establish a connection.
UDP: see User Datagram Protocol
UDPTL: Facsimile UDP Transport Layer protocol
User Datagram Protocol: The TCP/IP standard protocol that allows an application program on one machine to
send a datagram to an application program on another machine. Conceptually, the important difference between
UDP datagrams and IP datagrams is that UDP includes a protocol port number, allowing the sender to distinguish
among multiple destinations on the remote machine.
VAD: Voice Activity Detection
IP Media Server (Global Call) Demo Guide — November 2003
45
Download from Www.Somanuals.com. All Manuals Search And Download.
46
IP Media Server (Global Call) Demo Guide — November 2003
Download from Www.Somanuals.com. All Manuals Search And Download.
|