Like many software applications, Asterisk uses version numbers to indicate changes within the software. A new major version of the software is released approximately once a year. Each release version has an end-of-life that indicates when the developers will no longer maintain that version of Asterisk.

There are basically two different kinds of releases of the Asterisk system, a standard release and a Long Term Support (LTS) release. Standard releases are supported for at least one year with an additional year of security fixes. The LTS version is supported for 4 years, with an additional year of security fixes.

Below is a table showing the various releases of Asterisk:

Release Number	Release Type	Release Date	EOL
1.2.X		2005-11-21	2010-11-21
1.4.X	LTS	2006-12-23	2012-04-21
1.6.0.X	Standard	2008-10-01	2010-10-01
1.6.1.X	Standard	2009-04-27	2011-04-27
1.6.2.X	Standard	2009-12-18	2012-04-21
1.8.X	LTS	2010-10-21	2015-10-21
10.X	Standard	2011-12-15	2013-12-15
11.x	LTS	2012-10-25	2017-10-25
12.x	Standard	2013-12-20	2015-12-20
13.x	LTS	2014-10-24	2020-10-24
14.x	Standard	2016-09-26	2018-09-26
15.x	LTS	2017-10 (tentative)	2022-10 (tentative)

Similar to Asterisk, the Ubuntu Linux operating system releases standard and LTS versions. A new release comes out every six months, in April and September. Ubuntu releases an LTS operating system every two years, the last release in April of 2016. Both the Asterisk and Ubuntu LTS releases are often used by businesses. The latest Ubuntu LTS is version 16.04 and the Asterisk software available in it’s repository is Asterisk 13.