The Software Communications Architecture (SCA) was originally created by the Modular Software programmable Radio Consortium (MSRC): Raytheon, BAE Systems, Rockwell Collins, and ITT, under contract to the U.S. Department of Defense Joint Tactical Radio System (JTRS) Joint Program Office (JPO).
SCA version 1.0 was first introduced early in the year 2000 and was followed by revisions that culminated in the release of SCA v 2.0 later that same year. 2001 saw the release of version 2.2, time at which the specification was deemed ‘implementable’. With the knowledge gained by implementations developed during the newt two years, the specification was updated to version 2.2.1 in 2004. Version 3.0 was released later that same year, but work on such version was stopped one year later. Focus was returned to improve version 2.2.1, and version 2.2.2 saw the light of day in the year 2006. With more lessons learned through the following years, in 2009 work started towards the new version of the SCA. It was code named SCA Next, and 4.0 was released in 2012. The scope of improvements from version 2.2.2 to version 4.0 were substantial, and industry feedback identified backwards compatibility issues that needed to be solved. Version 4.1 is expected to be published towards the end of 2015.