How to configure QoS for VoIP

VoIP call quality depends on the callers having a stable, steady internet connection at an acceptable speed. Many internet-using services can benefit from QoS.

QoS, VoIP? What do those acronyms mean?

VoIP stands for Voice over Internet Protocol, a system that uses the internet to transmit data for telephone calls. Today, traditional telephone lines are almost completely phased out, and many people are using VoIP at home and at work, even if they aren't aware of it.

QoS stands for Quality of Service, a technology that helps prioritize internet traffic. Many internet connections are shared between multiple users who may be doing a variety of tasks, especially when it comes to business communications.

Workers might be browsing the web, watching videos and engaging in voice and video calls. QoS identifies what's most important and assigns the bulk of the connection's speed to that service.

How does QoS help with Call quality?

QoS can help reduce VoIP latency and maintain good call quality. Let's imagine you have one person browsing the web and occasionally downloading moderately sized files, while another person is on a VoIP call. VoIP is highly susceptible to jitter, lag, dropped packets and latency, so it's important the VoIP call has a steady speed.

By prioritizing the VoIP call, the router can maintain good VoIP latency. The person who is browsing pages or downloading files is unlikely to notice a small reduction in speed because they're using data in short bursts, reading something and then requesting a few more packets of data to download another page.

QoS means the router can keep the connection running with acceptable jitter for VoIP users, without necessarily impacting the experience for other users. QoS can be implemented for video calls, online gaming or anything that needs a stable connection, not just VoIP. Technology makes sharing a connection a much better experience for everyone.

How to configure QoS for VoIP

Acceptable VoIP latencies are typically between 50 and 65 ms, depending on the VoIP technology used. Anything more than this, and the lag is likely to impair the flow of any conversations. If you're experiencing issues with your connection and think they're caused by latency or jitter, QoS could greatly improve things.

Exactly how you enable QoS for VoIP depends on the type of router you have. Most consumer-grade routers will have a simple QoS section that gives you the option of either prioritizing specific devices by MAC address or prioritizing a specific port. In those cases, you'll either need to look up the MAC address of your VoIP phone (which is often printed on the bottom of the device) or find out what port is used for VoIP and set the QoS to prioritize traffic on that port.

Routers aimed at business users are usually more sophisticated. For example, the QoS on most Linksys routers supports configuring the upload bandwidth allocated to each port, making QoS for VoIP and other services manageable on a more granular level.

If you're interested in VoIP for business but don't want to have to worry too much about the technical details, take a look at the managed services we offer at 8x8. We provide technical support and a robust service level agreement, giving you peace of mind that your business communications will always work well. Contact us today to discuss your needs and get a free, no-obligation quote.