Main portion of the advantages of the Asterisk server appears from it being an open source downloadable product. Most of the users, especially business people, can find it difficult to understand the idea behind this principle, or free software, but a business models behind open source are different and specific, as in case with Asterisk server.
TERRATEL is a company providing services of designing embedded electronic and computing systems and telecommunication equipment: a full range of customized electronic design services of any complexity.