VPN and VoIP

There are a lot of reasons you might want to use a virtual private network (VPN) to carry (VoIP) traffic, but doing it the right way depends heavily on the details involved. While the obvious benefit is increased security, something which VoIP's underlying protocol, Session Initiation Protocol (SIP), there are other considerations especially when it comes to performance.

The reason for a specialized VPN has to do with the nature of voice traffic and with the specific requirements to make such traffic work efficiently across a business network. Those requirements include the ability to understand and leverage advanced network management tactics, like (QoS), which not only protects specific traffic types but also helps to reduce lag. That's a key capability for VoIP so you can enjoy freedom from undesirable network characteristics (such as jitter), and the ability to maintain a reliable connection so that users don't experience drops in service. Review your phone systems every 3-5 years.Why You Need QoSQoS is necessary because you need to ensure that your voice traffic consistently has the bandwidth it needs to function. Without it, network congestion may interrupt voice calls or it may degrade service to the point that it's unacceptable. And on the flip side, your VoIP traffic may also disrupt other applications that your workers need to do their jobs. Unfortunately, QoS settings don't normally survive once your connection leaves your internal network and reaches the internet.Low and consistent latency is a bigger deal than you may think, until you remember the last time you spoke with someone who was using a satellite phone. Then the delays involved made conversation difficult because you repeatedly had to pause your conversation to gauge whether or not the other person was speaking. It doesn't mean you can't communicate, but the conversation isn't natural.Addressing Security ConcernsIf what you're looking for is better security across your VoIP connections, then you may not need a VPN provider at all, as long as you can set up your own encrypted tunnel between offices. On the other hand, if you have remote workers who will be making VoIP calls from the field, then you may need a VPN provider that can handle such calls since you won't have full control over both ends of the connection.Avoiding JitterAnd, of course, you also need to avoid network problems such as jitter, which can make a voice call unintelligible. Jitter happens when packets arrive with differing latency, meaning that packets may arrive out of order, some may be dropped, and some parts of the voice communication may have delays when others don't. If you've ever heard a cell phone call when the caller's voice on the other end suddenly sounds broken up, with the voice making "burbling" sounds, then that's what jitter sounds like. And, of course, you want to avoid drops in service, but since you already use a cell phone, you know what that's like.For your business VoIP implementation, you'll need a VPN gateway that's designed to connect your network to another network. That other network can be a remote office or it could be in the office of an employee working remotely. What's important is that the VPN gateway be optimized for voice service. On most networks, whether you're running voice over your data network or whether you have a separate VoIP network, you should have a dedicated gateway for the VoIP VPN and nothing else.In addition, you should consider using a VPN service that's engineered specifically for VoIP communications. This is likely available from the VPN services we've reviewed, but you'll need to contact the company to ensure that the VPN service will meet your needs for the call quality you want. In addition, you will need to discuss the goals of your VoIP VPN with prospective providers. Do you need to make VoIP calls to countries where VoIP isn't permitted or are you simply trying to make sure your VoIP connection is secure?

This was produced by a business telephone systems expert for help with telephone systems contact me!