Asterisk - The Open Source VoIP PBX
Asterisk: The Future of Telephony
Table of Contents
Copyright
Foreword
Preface
Audience
Organization
Software
Conventions Used in This Book
Using Code Examples
Safari® Enabled
How to Contact Us
Acknowledgments
Chapter 1. A Telephony Revolution
Section 1.1. VoIP: Bridging the Gap Between Traditional Telephony and Network Telephony
Section 1.2. Massive Change Requires Flexible Technology
Section 1.3. Asterisk: The Hacker's PBX
Section 1.4. Asterisk: The Professional's PBX
Section 1.5. The Asterisk Community
Section 1.6. The Business Case
Section 1.7. This Book
Chapter 2. Preparing a System for Asterisk
Section 2.1. Server Hardware Selection
Section 2.2. Environment
Section 2.3. Telephony Hardware
Section 2.4. Types of Phone
Section 2.5. Linux Considerations
Section 2.6. Conclusion
Chapter 3. Installing Asterisk
Section 3.1. What Packages Do I Need?
Section 3.2. Obtaining the Source Code
Section 3.3. Compiling Zaptel
Section 3.4. Compiling libpri
Section 3.5. Compiling Asterisk
Section 3.6. Installing Additional Prompts
Section 3.7. Updating Your Source Code
Section 3.8. Common Compiling Issues
Section 3.9. Loading Zaptel Modules
Section 3.10. Loading libpri
Section 3.11. Loading Asterisk
Section 3.12. Directories Used by Asterisk
Section 3.13. Conclusion
Chapter 4. Initial Configuration of Asterisk
Section 4.1. What Do I Really Need?
Section 4.2. Working with Interface Configuration Files
Section 4.3. FXO and FXS Channels
Section 4.4. Configuring an FXO Channel
Section 4.5. Configuring an FXS Channel
Section 4.6. Configuring SIP
Section 4.7. Configuring Inbound IAX Connections
Section 4.8. Configuring Outbound IAX Connections
Section 4.9. Debugging
Section 4.10. Conclusion
Chapter 5. Dialplan Basics
Section 5.1. Dialplan Syntax
Section 5.2. A Simple Dialplan
Section 5.3. Adding Logic to the Dialplan
Section 5.4. Conclusion
Chapter 6. More Dialplan Concepts
Section 6.1. Expressions and Variable Manipulation
Section 6.2. Dialplan Functions
Section 6.3. Conditional Branching
Section 6.4. Voicemail
Section 6.5. Macros
Section 6.6. Using the Asterisk Database (AstDB)
Section 6.7. Handy Asterisk Features
Section 6.8. Conclusion
Chapter 7. Understanding Telephony
Section 7.1. Analog Telephony
Section 7.2. Digital Telephony
Section 7.3. The Digital Circuit-Switched Telephone Network
Section 7.4. Packet-Switched Networks
Section 7.5. Conclusion
Chapter 8. Protocols for VoIP
Section 8.1. The Need for VoIP Protocols
Section 8.2. VoIP Protocols
Section 8.3. Codecs
Section 8.4. Quality of Service
Section 8.5. Echo
Section 8.6. Asterisk and VoIP
Section 8.7. Conclusion
Chapter 9. The Asterisk Gateway Interface (AGI)
Section 9.1. Fundamentals of AGI Communication
Section 9.2. Writing AGI Scripts in Perl
Section 9.3. Creating AGI Scripts in PHP
Section 9.4. Writing AGI Scripts in Python
Section 9.5. Debugging in AGI
Section 9.6. Conclusion
Chapter 10. Asterisk for the Über-Geek
Section 10.1. Festival
Section 10.2. Call Detail Recording
Section 10.3. Customizing System Prompts
Section 10.4. Manager
Section 10.5. Call Files
Section 10.6. DUNDi
Section 10.7. Conclusion
Chapter 11. Asterisk: The Future of Telephony
Section 11.1. The Problems with Traditional Telephony
Section 11.2. Paradigm Shift
Section 11.3. The Promise of Open Source Telephony
Section 11.4. The Future of Asterisk
Appendix A. VoIP Channels
Section A.1. IAX
Section A.2. SIP
Appendix B. Application Reference
AbsoluteTimeout( )
AddQueueMember( )
ADSIProg( )
AgentCallbackLogin( )
AgentLogin( )
AgentMonitorOutgoing( )
AGI( )
AlarmReceiver( )
Answer( )
AppendCDRUserField( )
Authenticate( )
Background( )
BackgroundDetect( )
Busy( )
CallingPres( )
ChangeMonitor( )
ChanIsAvail( )
CheckGroup( )
Congestion( )
ControlPlayback( )
Curl( )
Cut( )
DateTime( )
DBdel( )
DBdeltree( )
DBget( )
DBput( )
DeadAGI( )
Dial( )
DigitTimeout( )
Directory( )
DISA( )
DumpChan( )
DUNDiLookup( )
EAGI( )
Echo( )
EndWhile( )
ENUMLookup( )
Eval( )
Exec( )
ExecIf( )
FastAGI( )
Festival( )
Flash( )
ForkCDR( )
GetCPEID( )
GetGroupCount( )
GetGroupMatchCount( )
Goto( )
GotoIf( )
GotoIfTime( )
Hangup( )
HasNewVoicemail( )
HasVoicemail( )
IAX2Provision( )
ImportVar( )
LookupBlacklist( )
LookupCIDName( )
Macro( )
MailboxExists( )
Math( )
MeetMe( )
MeetMeAdmin( )
MeetMeCount( )
Milliwatt( )
Monitor( )
MP3Player( )
MusicOnHold( )
NBScat( )
NoCDR( )
NoOp( )
Park( )
ParkAndAnnounce( )
ParkedCall( )
PauseQueueMember( )
Playback( )
Playtones( )
Prefix( )
PrivacyManager( )
Progress( )
Queue( )
Random( )
Read( )
RealTime
RealTimeUpdate( )
Record( )
RemoveQueueMember( )
ResetCDR( )
ResponseTimeout( )
RetryDial( )
Ringing( )
SayAlpha( )
SayDigits( )
SayNumber( )
SayPhonetic( )
SayUnixTime( )
SendDTMF( )
SendImage( )
SendText( )
SendURL( )
Set( )
SetAccount( )
SetAMAFlags( )
SetCallerID( )
SetCallerPres( )
SetCDRUserField( )
SetCIDName( )
SetCIDNum( )
SetGlobalVar( )
SetGroup( )
SetLanguage( )
SetMusicOnHold( )
SetRDNIS( )
SetVar( )
SIPAddHeader( )
SIPDtmfMode( )
SIPGetHeader( )
SoftHangup( )
StopMonitor( )
StopPlaytones( )
StripLSD( )
StripMSD( )
SubString( )
Suffix( )
System( )
Transfer( )
TrySystem( )
TXTCIDName( )
UnpauseQueueMember( )
UserEvent( )
Verbose( )
VMAuthenticate( )
VoiceMail( )
VoiceMailMain( )
Wait( )
WaitExten( )
WaitForRing( )
WaitForSilence( )
WaitMusicOnHold( )
While( )
Zapateller( )
ZapBarge( )
ZapRAS( )
ZapScan( )
Appendix C. AGI Reference
ANSWER
CHANNEL STATUS
DATABASE DEL
DATABASE DELTREE
DATABASE GET
DATABASE PUT
EXEC
GET DATA
GET FULL VARIABLE
GET OPTION
GET VARIABLE
HANGUP
NOOP
RECEIVE CHAR
RECORD FILE
SAY ALPHA
SAY DATE
SAY DATETIME
SAY DIGITS
SAY NUMBER
SAY PHONETIC
SAY TIME
SEND IMAGE
SEND TEXT
SET AUTOHANGUP
SET CALLERID
SET CONTEXT
SET EXTENSION
SET MUSIC ON
SET PRIORITY
SET VARIABLE
STREAM FILE
TDD MODE
VERBOSE
WAIT FOR DIGIT
Appendix D. Configuration Files
Section D.1. modules.conf
Section D.2. adsi.conf
Section D.3. adtranvofr.conf
Section D.4. agents.conf
Section D.5. alarmreceiver.conf
Section D.6. alsa.conf
Section D.7. asterisk.conf
Section D.8. cdr.conf
Section D.9. cdr_manager.conf
Section D.10. cdr_odbc.conf
Section D.11. cdr_pgsql.conf
Section D.12. cdr_tds.conf
Section D.13. codecs.conf
Section D.14. dnsmgr.conf
Section D.15. dundi.conf
Section D.16. enum.conf
Section D.17. extconfig.conf
Section D.18. extensions.conf
Section D.19. features.conf
Section D.20. festival.conf
Section D.21. iax.conf
Section D.22. iaxprov.conf
Section D.23. indications.conf
Section D.24. logger.conf
Section D.25. manager.conf
Section D.26. meetme.conf
Section D.27. mgcp.conf
Section D.28. modem.conf
Section D.29. musiconhold.conf
Section D.30. osp.conf
Section D.31. oss.conf
Section D.32. phone.conf
Section D.33. privacy.conf
Section D.34. queues.conf
Section D.35. res_odbc.conf
Section D.36. rpt.conf
Section D.37. rtp.conf
Section D.38. sip.conf
Section D.39. sip_notify.conf
Section D.40. skinny.conf
Section D.41. voicemail.conf
Section D.42. vpb.conf
Section D.43. zapata.conf
Section D.44. zaptel.conf
Appendix E. Asterisk Command-Line Interface Reference
!
abort halt
Section E.1. add
Section E.2. agi
Section E.3. database
Section E.4. iax2
Section E.5. indication
Section E.6. logger
Section E.7. meetme
Section E.8. pri
Section E.9. remove
Section E.10. restart
Section E.11. set
Section E.12. show
Section E.13. sip
Section E.14. stop
Section E.15. zap
Colophon
About the Authors
Colophon
Index
SYMBOL
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Index
[
SYMBOL
] [
A
] [
B
] [
C
] [
D
] [
E
] [
F
] [
G
] [
H
] [
I
] [
J
] [
K
] [
L
] [
M
] [
N
] [
O
] [
P
] [
Q
] [
R
] [
S
] [
T
] [
U
] [
V
] [
W
] [
X
] [
Y
] [
Z
]
A-law companding algorithm
use with G.711 codec
A/D (analog-to-digital) converter
abort halt command
AbsoluteTimeout( )
AbsoluteTimeout( ) application
adapters, telephony
Adaptive Differential Pulse-Code Modulation (ADPCM)
add command
add extension command
add ignorepat command
add queue member command
add-ons
AddQueueMember( ) application
adsi.conf file
ADSIProg( ) application
adtranvofr.conf file
AgentCallbackLogin( ) application
AgentLogin( ) application
AgentMonitorOutgoing( ) application
agents.conf file
aggressive residual echo suppression
AGI (Asterisk Gateway Interface)
debugging
fundamentals of communication
calling AGI script from dialplan
standard pattern of communication
STDIN, STDOUT, and STDERR
Perl AGI library
PHP AGI library
Python AGI library
reference
writing scripts in Perl
writing scripts in PHP
important steps to remember
writing scripts in Python
important steps to remember
agi debug command
2nd
agi no debug command
AGI( ) application
2nd
agi-bin/ directory
agi-test.agi script
alarm system for your home, controlling
AlarmReceiver( ) application
alarmreceiver.conf file
aliasing
alsa.conf file
alternating current (AC) voltage, analog phone ringer
AMD CPUs
IRQ latency and
power FPUs
analog circuits
Analog Display Services Interface (ADSI)
analog ground start lines
analog interface cards
analog interfaces
analog telephones
analog telephony
echo, why it occurs
parts of analog telephone
Tip and Ring wires
Analog Terminal Adaptor (ATA)
analog waveform, digitally encoding
analog waveform, digitization of
analog-to-digital (A/D) converter
answer command
2nd
Answer( ) application
2nd
3rd
Festival( ) application and
APIC-enabled motherboards, IRQ control
AppendCDRUserField( ) application
applications
AGI
Background( )
Congestion( )
Dial( )
extensions
s (start) extension
Goto( )
modules.conf file
reference
SayDigits( )
Zapateller( )
arguments (application)
Dial( )
Goto( )
arguments, using in macros
AstDB (Asterisk database)
deleting data
retrieving data from
rotating key for DUNDI information
storing data
using in the dialplan
astdb file
Asterisk
acceptance of
challenges to
community for development and support
compiling
configuring for Festival
directories used by
Documentation Project
future of
Internet Relay Chat (IRC) channels
loading
CLI commands
mailing lists
Manager
passing call control to an external program
sizes of systems
source code, obtaining
things now possible
VoIP
Wiki
asterisk package
asterisk program
-c (console) flag
-r (remote) flag
running with -h switch
asterisk-addons package
asterisk-sounds package
2nd
installing
Asterisk-users list
asterisk.conf file
Asterisk::AGI Perl module
ATA (Analog Terminal Adaptor)
audio
built-in components on motherboards
digital
quality problems on inadequate systems
audio formats, translation costs
audio streams, packetization for transport over IP networks
Authenticate( ) application
authentication
IAS FWD incoming calls
IAX connections
IAX protocol
inbound and outbound, Asterisk scheme
secret (password) in SIP
SIP
SIP client
with Manager
auto-attendants
Automated Attendant (AA), IVR vs.
Automatic Ringdown circuit
Asterisk