Versions of Asterisk
There are two different types of Asterisk releases: Long Term Support and Standard. The type of release defines how long it will be supported. A Long Term Support release is fully supported for 4 years, with an additional year of maintenance for security fixes. Standard releases are supported for a shorter period of time; one year of full support and an additional year of maintenance for security fixes. Releases for these versions are generally made every six to eight weeks.
Certified Asterisk releases have undergone additional testing and are made less frequently - typically two to four times a year. Certified Asterisk releases are generally identical to the Long Term Support release they are based on, save for additional bug fixes that were applied during testing. These branches can also include additional support, not available in the mainline releases, for Digium's IP Telephones.
Users new to Asterisk are encouraged to download the latest Long Term Support release, with the guidance that Certified Asterisk branches based on those releases have the least churn.
The following are the current supported Asterisk releases available for download:
|Release Series||Support Type||Release Frequency||Digium IP Phone Support|
|Asterisk 12||Standard||6 - 8 Weeks||Yes|
|Certified Asterisk 11||LTS||2 - 4 times per year||Yes|
|Asterisk 11||LTS||6 - 8 Weeks||Yes|
|Certified Asterisk 1.8||LTS||2 - 4 times per year||Yes|
|Asterisk 1.8||LTS||6 - 8 Weeks||No|
More information about the various versions of Asterisk is available on the Asterisk Versions wiki page. A complete listing of download options can be found on the Downloads Server. Information about installing Asterisk from source is available on the Installing Asterisk from Source Wiki pages.
Long Term Support (LTS) Releases
Long Term Support (LTS) releases are made from Asterisk branches where the focus has been on stability and user experience. New point releases include the latest bug fixes.
Standard releases are made from branches of Asterisk that received major new features. These branches are supported for a shorter period of time relative to LTS branches. Bug fix releases are made for one year, while security releases are extended for an additional year.
Test Releases are previews of the next versions of Asterisk. Each is in an alpha, beta, or a release candidate phase. Users who need to run the latest release for a bugfix are encouraged to test the test releases in their environments and provide feedback to the issue tracker.