When it comes to Voice over IP (VoIP), there’s plenty which can go wrong, and having been in the VoIP services business for many years, we tend to see the same issues pop up over and over. Below, we’ll review the three most common issues we deal with so you’ll know what to watch out for when you deploy a VoIP solution for you or one of your customers.
As we discuss in-depth in our “Voice Ready Internet” guide, there are several reasons which contribute to quality issues as it pertains to VoIP. Among them are:
- Jitter
- Latency
- Bandwidth
Of all the issues listed above, none is more regularly responsible for VoIP call quality issues than bandwidth and poor internet connection.
What Causes the Problems?
Jitter
Jitter happens when voice packets arrive out of sequence. Unlike traditional telephone which uses electrical signals to move voice calls across a wire, VoIP moves voice calls the same way data is moved across the internet – in data packets. For VoIP calls to sound clear, packets need to arrive in the correct sequence in real-time. Delays on the network and network congestion are common reasons data packets arrive out of sequence at the receiver’s side of the call. Since there is no one in control of the internet, this is a common and reoccurring problem.
Using jitter buffers is the simplest way to alleviate jitter. Jitter buffers can be either hardware or software based. The jitter buffer collects VoIP packets, assembles them in order and delivers to the receiving caller in the correct order.
Latency
Latency (or delay) can make a VoIP caller extremely frustrated. If you’ve ever been talking to the party on the other end of the line, heard an echo, or started talking at the same time, you’ve experienced latency.
As we discussed above, VoIP calls require real-time transmission. The time it takes for one endpoint to send a VoIP packet to the other end needs to be consistent for a good call to happen. Packet delivery is measured in milliseconds and the delivery time for a good VoIP experience is under 100 milliseconds.
Administrators with users complaining of echo are experiencing latency. The most common fix for latency issues is prioritization of data traffic. By utilizing prioritization and bandwidth management, regular data transmissions (think email, web surfing, Pandora radio, etc.) are sent to the “slow lane” as they are given a lower priority. Voice becomes high priority traffic and will be tagged and given the lion’s share of the bandwidth while the VoIP call is in progress. Once the call terminates, regular data transmissions can resume as before.
Bandwidth
Bandwidth is the single most misunderstood component of VoIP. All too often, bandwidth is purchased based on some cable company’s marketing brochure and the promo of the day! VoIP calls require at least 100k upload and 100K download speed to handle a single call.
Broadband internet typically touts a faster download and slower upload speed. Broadband services are also shared with everyone else in your local footprint, that’s how they make it cheap. When businesses are attempting to make and take several calls at once all while downloading files and sending email, calls are going to be “squeezed” and suffer from the issues described at the beginning of this article. It’s a simple matter of having enough room on the “road” to move everything at the speed these services need for a quality outcome.
Work with the VoIP Experts
Understanding how the internet handles VoIP traffic is the first step in ensuring a good voice experience for you or your clients. For more information about jitter, latency, or internet connections, download our Voice-Ready Internet guide below.