Asterisk Software

Build voice, video and text applications easily with Asterisk, the world's most widely adopted open source communications software development framework.

Certified Asterisk

Certified Asterisk is a branch of Asterisk supported by Digium for commercial SLA customers entitled under certain Support offerings. Like other branches of Asterisk, it is provided under GPLv2 license and may be used freely by anyone, even users and other customers who are not Digium’s SLA customers.

Releases are made at longer intervals, between 2 and 4 times annually, as opposed to the once-per-month cycle of mainline Asterisk releases; and are curated to minimize change and support longer quality assurance windows. This allows SLA customers to minimize the uncertainty of accepting large or frequent code updates. Each Certified Asterisk release begins as a selected mainline Asterisk point release that undergoes a rigorous and extended internal testing process. At the completion of the testing process, a new release is made, and SLA customers may begin receiving support, as dictated by their support agreements, on that release.

Releases of Certified Asterisk are made against the current Asterisk LTS codebase, presently 13, not against Asterisk Standard releases, e.g. 10 or 12, and represent a snapshot of the mainline Asterisk LTS release, branched and maintained with SLA customer bug fixes. Each release is versioned according to: asterisk-MainlineBranchPoint-certX, e.g. asterisk-13.1-cert2, where MainlineBranchPoint indicates the Asterisk release point at which the branch occurred and X represents the bug-fix release version of a particular release of Certified Asterisk. Bug-fix releases of Certified Asterisk are made for the duration of customer support agreements; and, following 1.8, new releases of Certified Asterisk have been made against Asterisk 11 and 13 LTS versions. This schedule provides customers the flexibility to migrate from one release to another, with overlapping support between major versions of Certified Asterisk.

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Certified Asterisk does not maintain feature differences from regular branch releases of Asterisk. Rather, Certified Asterisk is released on a different schedule than mainline Asterisk and is supported commercially by Digium under SLA contracts with customers that require engineering support, guaranteed bug fix resolution, and whose usage patterns does not line up with the frequent release schedule of mainline Asterisk.

Certified Asterisk FAQ

On which version of open source Asterisk is Certified Asterisk based?

The initial release of Certified Asterisk was based on Asterisk 1.8.11. The numbering for Certified Asterisk releases reflect the open source version from which they are built. For example, asterisk-1.8.11-cert1 was the first certified release, derived from Asterisk 1.8.11. Versions following the initial release have been made against both Asterisk 11 and Asterisk 13 releases.  For more information about the various versions of Asterisk, please see the Asterisk Versions wiki page.

How is Certified Asterisk different from regular open source Asterisk releases?

From a code perspective, Certified Asterisk is the same as a standard release of open source Asterisk. In order to help set SLA support customer expectations, Certified Asterisk disables, by default, compiling of non-Core modules, whereas releases of open source Asterisk may enable those modules by default. These modules may still be selected for compile manually, but they are not covered under customers' Service Level Agreements. For more information about Asterisk module support states, please see the Asterisk Module Support States wiki page.

Does Digium offer commercial licenses for Certified Asterisk?

Yes. Digium offers commercial licensing for Certified Asterisk releases. Digium also offers commercial licensing for all other releases of Asterisk. Commercial licensing and Support are not tied together. While Digium may offer commercial licensing of a version of Asterisk, e.g. 1.2, Digium only offers support for current open source versions and SLA support for Certified Asterisk releases.

What is the benefit of using Certified Asterisk if I'm not a Digium customer?

There are no special benefits to using Certified Asterisk for users or customers that are not under an SLA with Digium. If your needs as an open source user align with those of SLA customers, you may use Certified Asterisk under the terms of the GPLv2, just as with standard open source releases of Asterisk.

How would I submit an issue report for Certified Asterisk?

SLA customers are provided with Support contacts as a part of their agreement for the purposes of reporting issues to Digium. Issues reported by SLA customers and resolved by Digium will trigger point releases of Certified Asterisk. Issues reported by users who are not SLA customers will not trigger point releases of Certified Asterisk.

How do I download Certified Asterisk?

Certified Asterisk is available as RPM packages from or as source code from or

How do I buy a support SLA and/or proprietary license for Certified Asterisk?

Please contact the Digium Sales department to discuss your needs and our offerings.

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