Manging Very Fast VoIP Traffic With Virtual LANs or VLANs

Managing your VoIP traffic over the internal network can require some technical skills. In the simplest scenario of course, VoIP doesn't need any management. It can just coexist with your regular Internet connection and indeed in many businesses, this is the case. However, we all know that VoIP traffic has different specifications compared to normal web traffic with regard to timing and priority. Therefore, it makes sense to implement network rules that give it this special treatment. In addition, security policies should be specifically tailored to prevent the misuse of Voiceover IP.

Today, we discuss a powerful way of managing your VoIP traffic - Virtual LANs or VLANs.

VLANs are a way of segregating your network into different parts depending on the parameters used. If you had to do this physically, you would need to connect a separate set of cables between the devices. Virtual LANs work at the software level and thus don't need dedicated lines. Of course, this won't increase the overall bandwidth of the system, but modern LANs are so fast it's usually not necessary to add more.

Network managers can benefit from configuring the network in such a way that all VoIP traffic goes through a separate VLAN network. This allows a fine control over various parameters. For example, we can instruct the switches to prioritize VoIP data over regular data thus allowing us to maintain a Quality of Service (QoS) of sorts since we can specify that a certain amount of bandwidth should always be available to VoIP no matter what the traffic is like on the other LAN.

Another benefit is that we can configure security policies which are dedicated to VoIP traffic. This allows us to take precautions against common threats such as man in the middle attacks as well as protect ourselves from hackers who try and steal VoIP minutes. Of course, if you're using a good Hosted PBX solution there's no need for the latter precaution. But it's still a good idea to have internal VoIP security policies.

VLANs can be implemented in many ways. Cisco for example specializes in providing VLAN hardware switches which work exceptionally well with Cisco VoIP phones. In a later article, we'll see how to configure these switches for optimum performance as well as how to make them work well with phones from other companies.

So as a first step to managing your VoIP traffic, create a VLAN that's dedicated to it.