Thursday, February 14, 2008

VoIP Without The Internet

VoIP or Voice over Internet Protocol telephony made its name as an Internet based telephone service alternative. The idea was to use the broadband connection that most residential and business users had in place to also connect with their phone service provider. Competitive service providers could avoid paying the local telephone companies to lease the existing copper phone lines and offer a better bundled price to customers. In theory, it should be easy for the gigantic Internet pipe to transport low bandwidth voice streams.

Well, that's the theory. In practice, that big pipe isn't always so infinitely large. Like the super highway it emulates, Internet paths can become congested with packets just as easily as highways become congested with cars. Bandwidth congestion, transmission delays called latency, and dropped packets can easily tear up a phone conversation or any other type of real time data stream.

Most of the problem is in the infamous first-mile. That's the connection between your location and your service provider's point of presence or POP. Shared bandwidth arrangements such as DSL and Cable broadband make no guarantees as to availability or quality of service. One minute everything is working great. Next minute the line goes dead. Or at least the conversation gets garbled from time to time.

Consumers might put up with this level of performance if they can save enough money on their phone bill. But businesses really can't afford the customer annoyance and lost connections during important conversations. Having experienced problems with VoIP installations or hearing horror stories has convinced many businesses to hunker down and avoid the entire network voice issue. Others have worked out arrangements so that they can have the best of both worlds. They get the reliability and voice quality they've come to expect from the public switched telephone network. Plus the cost savings and added features that come from a converged voice and data network.

How do the successful businesses do it? For many the secret is as simple as avoiding the Internet for anything but Web and email access or electronic data interchange. But that doesn't have to mean maintaining a bank of analog phone lines and an ancient telephone system. There are at least two ways to have your VoIP without having to eat the problems too.

The first approach is to go with a hybrid PBX phone system. Within your plant, the phones and switch are IP based. SIP telephones and an IP PBX system allow you to use a single Ethernet LAN to connect both computers and phones. Yes, you'll need to carefully engineer your network to make sure that voice packets move unrestricted. But that may well be worth the effort to eliminate the separate telephone network and all its maintenance expense. With the hybrid approach, IP stops at the IP PBX. Plug-in interface cards for T1 PRI trunks or simple analog lines bring in conventional telephone service.

The second approach is to employ SIP trunking to connect your IP PBX to your competitive phone service provider. SIP trunking is a private line arrangement that maintains the integrity of the VoIP packets all the way from telephone set to service provider. The SIP trunk is usually shared with Internet data coming from the service provider to your network. However, your voice packets never traverse the public Internet. They stay on the SIP trunk until they are terminated to the public telephone network by your provider. You are never in contention with other users for the bandwidth that transmits your voice and data packets.

Both of these approaches give you control over Quality of Service for your telephone calls. Either you connect to the public phone network at your company location. Or your send your call streams to your service provider over a carefully engineered private line. It avoids the contention and variability that are inherent to that public facility that is the Internet.

Are you interested in improving your business telephone system but concerned about maintaining quality and reliability. Let our expert consultants recommend alternative approaches that address those concerns but also offer capital and operational cost savings. Tell us about your needs at

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