Asterisk is a free and open source framework for building communications applications and is sponsored by Digium.
FreePBX is a web-based open source GUI (graphical user interface) that controls and manages Asterisk.
Here's why we use Asterisk®/FreePBX Open Source Software
FreePBX features our customers enjoy
ACD (Automatic Call Distribution)/Call Queues
Announcements
Auto-Attendant/VR
Automatic Backup
Black List
Bulk Import Utilities
Busy Lamp Field (BLF) Support
Call Detail Reporting
Call Flow Control
Call Forwarding
Call Monitoring
Call Parking
Call Recording
Call Screening
Call Spy
Call Transfer
Callback Services
Caller-ID
Camp-On
Centralized User Management
Company Directory
Conference Rooms
Customized Voice Prompts
Dictation
Direct Inward System Access (DISA)
Do Not Disturb
Extensions Management
Fail2ban
Fax to Email
Feature Codes
Follow Me
Graphical Reports
Hunt/Ring Groups
Integrated Faxing
Multiple Language Support
Multiple Offices
Multiple Trunks
Music on Hold
Operator Panel
Outbound/Inbound Routes Management
Paging and Intercom
Phone Directory
PINSets
Remote Users
SIP-Open Standards
Soft-Phone Support
Speed Dials
SRTP
System Status Dashboards
Three Way Calling
Time Conditions
TTS-Text to Speech
Unlimited Extensions
Unlimited IVR ports
Unlimited IVR
Unlimited VM Messages
User Control Panel
Video Calling
VMX Locater
Voicemail
Voicemail to Email
Wake Up Calls
Web Based Administration GUI
