The Basics of VoIP Systems

Installing VoIP systems makes sense for CE pros — if you do it this way.

Fred Harding · October 14, 2009

There are several applications for voice over Internet protocol (VoIP) in the custom installation field, so one size does not fit all.

It’s a good idea to communicate with your client about expectations and applications before making blanket recommendations.

How VoIP Works

Essentially, VoIP technology communicates conversations over the Internet. The most common application uses a product from a provider like Vonage, which essentially hooks up to a high-speed Internet modem and provides a plain old telephone dial tone connection. The primary motivation for deploying a Vonage-style system is to reduce costs.

That type of setup can be deployed with a telephone system, commonly called a KSU (key serving unit). The installation chain goes from high-speed modem connection to VoIP box to the incoming telephone company connection on the KSU. Since the VoIP box provides a dial tone, the end user sees no difference in operation other than a lower long distance bill.

One potential drawback with VoIP technology that has been addressed reasonably well is the idea of 911 emergency calls. Essentially, user addresses are now electronically identified with an address from a VoIP caller, so help can be dispatched on an as-needed basis.

Remote Communication

Another application for VoIP technology that’s becoming increasingly popular involves remote offices communicating with central offices. In one application I’m familiar with, an employee works from his home 75 miles from the office. Using VoIP technology, the remote employee has access to the main office’s voicemail and KSU through a proprietary telephone connected to a DSL connection.

When end users call the main office, calls can be transferred to the remote extension with complete transparency. Messages left in voicemail at the central office light up at the remote extension. Intercom calls allow easy communication between departments. With that technology, the remote employee can actually check in to the telephone system from any high-speed Internet connection around the world using a proprietary telephone.

An additional really cool option allows the end user to add a license to their laptop with the addition of a headset/microphone combination to create a virtual telephone. You can see the guy now at the airport terminal, checking voicemails, talking loudly and disturbing all the other passengers around him.

This technology requires a specific KSU with appropriate cards and proprietary telephones to deploy. Manufacturers like NEC, Panasonic and Mitel offer this type of product. Installers may be required to go through certification programs to purchase and install these systems, so research the specific manufacturer before assuming you can do the installation.

Anytime VoIP modules are deployed, it’s important to remember that you will need to consider power failures. A battery backup is strongly advised for both the Internet modem connection and the breakout box. Plain old corded phones still operate during most power outages, and your customers likely will expect that same level of service.

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  About the Author

Fred Harding is in sales and technical support at Capitol Sales, a full service distributor of electronic installation hardware. He is a frequent contributor to CE Pro, writing hands-on product reviews and technical tips. Have a suggestion or a topic you want to read more about? Email Fred at

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  Article Topics

News · Phone · All Topics
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