Asterisk is #13 in Top 10 Business Phone systems
An open source telephony switching and private branch exchange service for Linux. Information on downloading, installation of and support for the product. Asterisk is like a box of Legos for people who want to create communications applications. It includes all the building blocks needed to create a PBX, an IVR system, a conference bridge and virtually any other communications app you can imagine.
Positions in ratings
#13 in Top 10 Business Phone systems
Alternatives
The best alternatives to Asterisk are: FreeSWITCH, FreePBX, 3CX, Avaya