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Designing a Quality VoIP Line Solution with 3CX

One of the things I love most about 3CX is the ease with which you can add VoIP lines.  It’s quick and easy to create multiple VoIP lines for different purposes such as, long distance providers for outbound calls or to tie in local numbers from anywhere in the world.  From a customer perspective, the flexibility and cost savings that come with a VoIP line are extremely attractive.

There are typically two concerns I hear from customers with using VoIP lines:

  1. Call quality can sometimes be an issue since your call traverses the general Internet
  2. If the Internet connection fails then you lose both voice and data connections

In my experience, both of these issues can be addressed, thus providing a VoIP line solution that delivers crystal clear audio and, in many cases, with more overall reliability than a pure POTs/PRI solution.

Here’s how…

Ensuring voice quality on a VoIP Line:

There are obvious things you can do to ensure as much voice quliaty on your VoIP line as possible.  Such as, configuring QoS on your edge routers and switches, providing sufficient Internet bandwidth and choosing a VoIP provider that has a reliable system on their end.  But you cannot control, is what happens between you and that provider and this is where many of the quality issues come into play.

At Worksighted, we have been successful in finding at least one local ISP in our area that is also a VoIP provider.  More specifically, they have in-house VoIP/PSTN conversion.  Meaning, the voice traffic has to only go one hop upstream before being placed onto the PSTN.  This ensures a hihh degree of voice quality since the ISP has complete end-to-end control of the voice traffic while delivering all of the other benefits that expect to see with a VoIP line.  I believe we will see more ISPs beginning to offer these services and a little looking around in your local area may be deliver big benefits.

Implementing 2-way PSTN disaster failover with your VoIP line:

When a customer has a need for 99.999% uptime for their voice lines, they tend to get a little shakey considering a VoIP provider as the main trunk service even though the features of the service (and cost) may be attractive.  When this happens, I typically recommend the addition of a 4 port POTs/PSTN gateway to provide 2-way failover.

Consider the following…

Not only is it simple to configure VoIP lines in 3CX but it’s also a snap to program a supported PSTN gateway device.  This gives you two different paths to send outbound calls on.  But how do we make this seemless to the user dialing their phone?  The trick is to leverage the outbound rules in 3CX and make the PSTN gateway device a secondary route on the rule that you already have for your VoIP line.  Suddenly, your users dont know the difference, the Internet connection can be down and their calls seemlessly failover to the POTs lines.  But what about incoming calls?  Good question!

If you have the phone company place your four emergency POTs lines into a hunt group then incoming calls on line 1 will role over to 2,3 or 4 if the previous line is occupied.  This is traditional phone company hunt group behavior.  If you now talk to your VoIP provider and ask them to forward calls on your VoIP line to the number of the Hunt group form the phone company in the even that your PBX is unreachable to them…..voila!  We now have a complete 2-way failover solution for 3CX.

Additionally, we would have to lose our Internet connection AND our POTs lines to fail to be able to make and receive calls which is, of course, highly unlikely and less likely than if we were serviced with only POTs lines!!

I hope you have found this article helpful!

Happy 3CXing!!!!



By |November 11th, 2008|Comments Off on Designing a Quality VoIP Line Solution with 3CX

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