Asterisk an open-source framework for building communications applications. It runs on Linux, BSD and OS X and allows you to build a PBX given sufficient Linux and telephony know-how. Asterisk does voice over IP in four protocols and can interoperate with almost all standards-based telephony equipment using relatively inexpensive hardware.
Asterisk provides Voicemail services with Directory, Call Conferencing, Interactive Voice Response, Call Queuing. It has support for three-way calling, caller ID services, ADSI, IAX, SIP, H.323 (as both client and gateway), MGCP (call manager only) and SCCP/Skinny. Check the Features section for a more complete list.
Asterisk needs no additional hardware for Voice-over-IP, although it does expect a non-standard driver that implements dummy hardware as a non-portable timing mechanism (for certain applications such as conferencing). A single (or multiple) VOIP provider(s) can be used for outgoing and/or incoming calls (outgoing and incoming calls can be handled through entirely different VOIP and/or telco providers)
Lastly, standalone devices are available to do a wide range of tasks including providing fxo and fxs ports that simply plug into the LAN and register to Asterisk as an available device. If you are looking for a ready to go solution for Windows or Linux, 3CX offers a highly-regarded product.
Books
- Addison-Wesley
- The Asterisk Book – Practical Asterisk 1.4 – GNU FDL, completely available online
- Das Asterisk Buch (German) – Asterisk 1.2 + 1.4 – GNU FDL, completely available online
- Learning Guide for Asterisk 1.6 (English) Asterisk 1.4 and 1.6 – Released in June 2010
- Asterisk: The Future of Telephony – Brought To You By The Asterisk Documentation Project – FREE DOWNLOAD!
- Switching to VoIP – Ted’s book is full of Asterisk know-how
- T1: A Survival Guide – Not specifically about Asterisk, but if you want to understand T1s, this is the book
- Construindo Sistemas de Telefonia com o Asterisk Asterisk book in Portugues released.
- Construyendo Sistemas telefónicos con Asterisk Asterisk book in Spanish released.
- Latest Asterisk Book Building Telephone Systems With Asterisk
Introduction
- Asterisk introduction: An overview for new Asterisk administrators – THE PLACE TO START!!
- Asterisk installation
- Asterisk Mailing Lists
- Asterisk software addons
- Asterisk tips and tricks: Solutions to common problems, hints of what you can do with this powerful software
- Series of video tutorials about Asterisk dial plan development
- FAQ and SEARCH helper: Look for answer to the question that bugs you here!
- Free video tutorials about Asterisk dial plan
- News, Project status and roadmap
- VoIP User Groups: Local resources in your area
- Where to download Asterisk
Hardware
- Asterisk Appliances
- Asterisk and Cable Modems with embedded ATAs: How to connect an embedded ATA to Asterisk
- Asterisk and Virtual Private Servers: How to run Asterisk on a VPS/VDS}
- Asterisk and VoIP Gateways: A list of many manufacturers of VoIP gateways
- Asterisk Blades: Standalone Asterisk-based PCI cards
- Asterisk dimensioning: How big a processor do I need and what call load can my system handle?
- Asterisk embedded systems: Asterisk on no-frills hardware
- Asterisk hardware: Hardware known to work with Asterisk]
- Asterisk legacy integration: How to integrate Asterisk and an ordinary PBX
- Asterisk phones: Common phones in use together with Asterisk
- Asterisk text: Text communications support in Asterisk
- Asterisk video: Video call support in Asterisk
- Hardware use cases: Hardware recommendations for different needs & success stories
Administration and system layout
- Asterisk administration
- Asterisk at large: Tips for large installations (SIP proxy, load balancing)
- Asterisk billing support
- Asterisk Bootable CDROM: Boot and run Asterisk from a CDROM
- Asterisk configuration from database
- Asterisk configuration from template files
- Asterisk dimensioning: What CPU do I need, how many concurrent calls does my hardware support?
- Asterisk encryption: About SRTP, TLS and IAX encryption
- Asterisk fax Asterisk and Faxing
- Asterisk groups: The various and confusing group concepts in Asterisk.
- Asterisk High Availability Design: High Availability and Clustering Design and Issues
- Asterisk High Availability Solutions: Hardware and software solutions to increase availability.
- Asterisk Install CDROM: Simultaneously install an OS and Asterisk from one CDROM — easiest and quickest way to get Asterisk up and running.
- Asterisk monitoring: Making sure it stays up
- Asterisk OS Platforms: What Operating Systems Asterisk works with
- Asterisk password files: Where can you find users and passwords in Asterisk configuration files?
- Asterisk PBX functions: Introduction that helps you find common PBX functions in Asterisk
- Asterisk rollout tips: Tips on how to move from testing to practical rollout.
- Asterisk security: Security in the PBX
Configuration
- Asterisk – documentation of application commands: The complete cross-reference!
- Asterisk AEL: Asterisk Extension Language
- Asterisk AEL2: Asterisk Extension Language – version 2
- Asterisk AGI: Powerful programmatic scripting interface
- Asterisk config files: Overview of the Asterisk configuration files
- Asterisk Configuration Examples: Complete Asterisk configuration examples from various users
- Asterisk configuration from database
- Asterisk configuration from template files
- Asterisk phones
- Asterisk Configurations for connecting with VOIP providers: How to connect Asterisk to VOIP providers
- Asterisk Data Configuration: Zaptel and Asterisk data and hybrid configuration
- Asterisk database: The built-in database used in the dialplan
- Asterisk functions: The Functions used in 1.2
- Asterisk Slimming: How can we slim-up about so many modules
- Asterisk tips and tricks: Many config tips
- Asterisk variables: Variables used in configuration and dial plan
Management
- Asterisk CLI: The interactive command prompt language
- Asterisk GUI: Web and other interfaces to Asterisk for management and configuration
- Asterisk manager API: The Asterisk Manager API
- Asterisk options: Command-line switches when you start your Asterisk PBX
- Asterisk Zeroconf Support: Service Discovery for Asterisk using Zeroconf
- Asynchronous Javascript Asterisk Manager (AJAM) – HTTP Manager API Access
Troubleshooting
- Asterisk debugging: How to debug Asterisk
- Asterisk PCI bus Troubleshooting: Troubleshooting PCI bus issues (Especially those related to the Digium TDM400P)
- Asterisk PSTN interface debugging: Echo problem, signal level issues, etc.
- Asterisk Voice Delay: Options to reduce the delay between voice transmission and receipt
General Reference
- Asterisk codecs: Supported codecs
- Asterisk channels: Supported voice channels
- Asterisk International: How to make * work outside the USA
- Asterisk libpri: Open Source PRI library
- Asterisk multi-language: Tips on configurations for multi-language installations
- Asterisk Paging and Intercom
- Asterisk protocols: Supported protocols
- Asterisk sound files: Standard sound files and their meaning
- Asterisk vertical service activation codes: *XX codes used on Zap Channels
User Groups
- Asterisk Army: Asterisk User Map – Forum
- AsteriskCounter: Page that counts how many users uses Asterisk
- Asterisk Professionals: Certified Asterisk Professionals and Instructors
- Asterisk User Groups Hang out with Asteristas in your area!
- VOIP Today Community Providing the success and use of Asterisk also FREE Asterisk support.
- VoIP User Groups: Local resources in your area
Interesting and Unusual Projects
- Village Telco Using Asterisk in a WiFi Mesh network to provide phone service in rural areas
Howtos and Tutorials
- Asterisk settings for Localphone: How to configure Asterisk to work with Localphone’s VoIP service ((SIP/IAX Services for Asterisk)): Where to obtain VoIP Services for Asterisk Platform
- Series of video tutorials about Asterisk dial plan development
- Asterisk auto-dial out: How to make your PBX dial out automatically
- Asterisk Cisco 79XX XML Services: How-To Create XML scripts for Cisco 79XX Phones
- Asterisk Cisco CallManager Express Integration: How-To integrate Asterisk with Cisco CallManager Express
- Asterisk Cisco CallManager Integration: How-To integrate Asterisk with Cisco CallManager
- Asterisk Voicemail Notify for Support Numbers: Asterisk Voicemail Notify for Support Numbers
- Integrating the Power of Open Source Telephony with Web 2.0 Technology
Phone System 