Asterisk

Summary

Asterisk is a free, open-source framework for building communications applications. It can turn an ordinary computer into a communications server and powers systems such as IP PBX, VoIP gateways, conference servers, call centers, voicemail and IVR. Listed functions include routing, recording, queuing, conferencing, voicemail, automated attendants and call transfers. It offers computer-telephony interfaces including AGI, AMI and ARI, and supports protocols such as SIP, H.323, IAX, Jingle/XMPP, MGCP and SCCP. Asterisk can connect communications to applications, including CRM systems through AMI. Its source code can be downloaded, and the project points users to installation on a modern cloud Linux instance. Building applications with Asterisk requires working knowledge of Linux, scripting, networking and telephony. It is distributed under GPLv2; Sangoma offers commercial licensing for uses incompatible with that license. Community help is available through the Asterisk forum.

Who it is for

Asterisk suits people building communications systems who are comfortable with Linux, scripting, networking and telephony. It may also fit organizations that need to connect telephony with applications such as CRM systems.

Compared on interactive voice response software

Free plan

Yesasterisk.org

Facts

Purpose

Asterisk is an open source framework for building communications applications and turns an ordinary computer into a communications server.asterisk.org · 4 Oct 2026

Use cases

Asterisk powers IP PBX systems, VoIP gateways, conference servers, call centers, voicemail servers and IVR systems.asterisk.org · 4 Oct 2026

Features

Its listed features include call routing, recording, queuing, conferencing, voicemail, IVR, automated attendants and call transfers.asterisk.org · 4 Oct 2026

Interfaces

Computer-telephony interfaces include AGI, AMI and the Asterisk REST Interface (ARI).asterisk.org · 4 Oct 2026

Protocols

Listed VoIP protocols include SIP, H.323, IAX, Jingle/XMPP, MGCP and SCCP.asterisk.org · 4 Oct 2026

Integrations

The site says Asterisk can connect communications to applications, including Salesforce automation or CRM systems using AMI.asterisk.org · 4 Oct 2026

Deployment

Asterisk can be downloaded as source code, and the site points users to install it on a modern cloud Linux instance.asterisk.org · 4 Oct 2026

Linux requirement

The site says building applications with Asterisk requires working knowledge of Linux, scripting, networking and telephony.asterisk.org · 4 Oct 2026

Licensing

Asterisk is distributed under GPLv2 and Sangoma offers commercial licensing for uses that are incompatible with GPLv2.asterisk.org · 4 Oct 2026

Support

Sangoma offers five support levels for core components of current open source Asterisk versions, with Level 5 reserved for customers requiring an SLA and engineering support.asterisk.org · 4 Oct 2026

Community help

The Asterisk forum offers community help and feedback on installation, upgrading and running Asterisk.asterisk.org · 4 Oct 2026

Notable limitation

MFC-R2 is listed as not supported, although the page says a patch is available.asterisk.org · 4 Oct 2026

Sponsor

Asterisk is sponsored by Sangoma.asterisk.org · 4 Oct 2026

Company

Founded

1999asterisk.org · 28 Sept 2026

Where it ranks on Everything Xiaomi

• Best Interactive Voice Response Software in 2026#5 of 20

Sources

• asterisk.org/get-started/· checked 4 Oct 2026
• asterisk.org/get-started/applications/· checked 4 Oct 2026
• asterisk.org/get-started/features/· checked 4 Oct 2026
• asterisk.org/downloads/· checked 4 Oct 2026
• asterisk.org/products/software/licensing/· checked 4 Oct 2026
• asterisk.org/support/· checked 4 Oct 2026
• asterisk.org· checked 4 Oct 2026
• asterisk.org/products/software/· checked 4 Oct 2026