Thinking of implementing Asterisk, Asterisk Business Edition or TrixBox (Formerly Asterisk @ Home)? Asterisk is growing in popularity as a viable alternative to often expensive, proprietary IP PBX solutions from tier 1 vendors. Asterisk is open source software which is maintained by Digium as well as a host of volunteer coders around the globe.
If you are new to open source telephony, below are a few good places to begin learning about these technologies:
With the advent of various GUIs (Graphical User Interfaces) for Asterisk, the barriers to entry for businesses and other users lacking Uber-Geeks in the backoffice are slowly being removed. Asterisk supports both SIP and IAX protocols for VoIP calling, with SIP being the most commonly used.
In addition to the Asterisk software and Linux variant operating system, you’re going to need some basic hardware elements to get started. Asterisk is commonly hosted on a server, which can be a desktop type PC, or a more industrial, rackmount type server.
Both Intel and AMD based machines will work. Configured properly, Asterisk is not an extremely “resource intensive” application, and can run on a fairly lean hardware configuration. A good base system would require:
- Intel or AMD 2.0 GHz CPU
- 512MB RAM
- 20GB or Larger SATA or EIDE Hard Drive
- CD-Rom, Video Card, Sound Card, 10/100 Ethernet Card
- At least one free PCI or PCI-X Expansion Slot
Asterisk is commonly deployed in a “hybrid” scenario, with calls being placed via VoIP, as well as over the PSTN. Digium, Sangoma and Rhino produce PCI interface cards allowing for PBX connectivity to the legacy PSTN, as well as digital T1/PRI, E1 and ISDN/BRI. Analog cards are available with FXS Ports, FXO ports, or a combination of both. Additional upgrade modules providing echo cancellation are also available. Some Digium PCI cards require a specific voltage PCI slot, either 3.3V or 5V. Be sure to adequately research your motherboard prior to purchasing a Digium PCI board.
Asterisk supports the use of both IP enabled telephones, as well as traditional analog telephones used in conjunction with an ATA (Analog Telephone Adapter), Gateway or Channel Bank. IP Enabled telephones can be connected directly to the network, whereas analog telephones are going to require a bit of extra hardware to connect to your Asterisk server.
Popular SIP phones for use with Asterisk include:
In future posts, we’ll explore setting up Asterisk, and performing basic configuration on the various hardware elements involved.