In part one of this series on setting up a SOHO Voip solution, I detailed the requirements that we had for choosing the components of our system. In this section I’ll get into the network and hardware components required to set this system up, along with their layout.
Surprisingly during my research for this project, I had a difficult time finding a clear outline of what exactly was needed to set up this system. It turned out that I needed much less than most guides lead me to believe. Of course this depends on your requirements but in my scenario I wanted a strictly voip system with SIP phones and would not tie at all into an analog provider or telephone line. That greatly reduces the complexity of the system and lowers the requirements.
What you need
- Broadband internet connection. The more call volume you have the higher the bandwidth you will need. We have low call volume and are using a 7Mbps/700Kbps connection, this has been plenty of bandwidth for us.
- Wired Ethernet router. You have a ton of options here but your budget will likely decide this one. I’d suggest a decent VPN router that has QoS and a good amount of concurrent connection volume. The VPN function will come in handy if you want to use your VOIP system from a remote office or home office. We went with the ZyXEL ZyWALL 5 Internet Security Firewall Appliance
and have been very pleased. It is an excellent value.
- A computer to act as the PBX Server. The requirements for this system are very low unless you have a lot of phone users. Our machine is modest and has still been overkill, it has a 3Ghz P4 processor, 1 GB RAM, 10/100 Ethernet, and 120 GB Hard drive. We bought it for $80 through Geeks.com and it works perfectly.
- IP Phones. There are a slew of IP phones out there from full color touch screen ones to wifi cordless ones. Just double check that the phones you choose are compatible with the PBX server you choose. We have about a dozen Mitel 5224 IP Phone (Dual Mode) – VoIP phone – SIP
phones operating in SIP mode that work great with our system.
- PBX Server Software. The PBX software is what gets installed on your server to act as the brains of your local phone network. It allows you to do everything you can imagine with your phone system. We are using the Asterisk PBX system with Free PBX as the user interface. Both are free and can be installed together in about 15 minutes by using the AsteriskNow .iso image available at Asterisk.org.
- VOIP Provider. This is a service that you need to subscribe to, much like a normal phone company, that allows you to actually make and receive calls outside of your office. Without one of these you’re only able to dial other extensions within your office. We went with a provider named Callcentric for no real reason other than they are cheap and let you set up an account for free to make sure your system is working first before you subscribe. We currently pay $8.95/month for unlimited incoming calls and we use the Pay-as-you-go plan for outgoing which is pretty common for this type of service. So far we’ve spent a whopping $1 on outgoing calls.
The network layout for this system looks like this:
Notice how the PBX server doesn’t connect to anything directly? In the next part of this series I’ll discuss the setup of these components to get the system up and running.