If you are using a VoIP phone system, it is almost a certainty that you have experienced poor call quality. This article discusses the causes of VoIP call quality problems and what you can do to correct them.
The causes of poor quality VoIP calls are easy to diagnose and correct. Your telephone system provider in conjunction with your VoIP Service Provider should be able to identify and work with you to correct these problems. More importantly, these problems should not be ongoing. If your telephone system or VoIP Service Provider are unable to correct your call quality problems, you need to find different providers.
5 Most Likely Causes of Poor Quality VoIP Calls and How You Can Fix Them:
1. The Problem: Poor Internet Connection
Running VoIP over a public Internet connection can be done but it is not recommended for best performance. Most ISP’s are designed for web surfing and not VoIP advantages. Transporting voice packets is different and requires an additional set of internet protocols that your ISP may not be providing. Trying to squeeze multiple VoIP channels down an already congested ADSL connection will always result in poor performance.
The Solution: A proper Business Class connection offering guaranteed performance
Fortunately, most of the ISP’s, including cable and DSL high speed internet providers offer business class connections.
2. The Problem: Inadequate Router
Bad equipment is bad equipment.
The Solution: Install a Specialised VoIP Router and/or firewall
This is one of the most common causes of call quality issues. Many small businesses use their internet connection for both voice and data. This is perfectly fine as long as your router has the ability to prioritise VoIP traffic.
Without a router that is configured for packet prioritisation, call quality can be impacted by the other users on your network. For example, if during a call, another user on your network downloads a large file, without packet prioritisation, your call quality could be degraded. A VoIP router prevents this from happening by giving priority to voice traffic on your network.
VoIP routers are not an expensive piece of hardware.
3. The Problem: Jitter
Jitter is a common problem of the connectionless networks or packet switched networks. Because the information (voice packets) is divided into packets, each packet can travel by a different path from the sender to the receiver. When packets arrive at their intended destination in a different order then they were originally sent, the result is a call with poor or scrambled audio.
Jitter is technically the measure of the variability over time of the latency across a network. Jitter is one of the most common VoIP call quality problems.
The Solution: Turn on your Jitter Buffers
A jitter buffer temporarily stores arriving packets in order to minimise delay variations. If packets arrive too late then they are discarded resulting in a minor loss that the ear all but ignores.
4. The Problem: Latency
VoIP delay or latency is characterised as the amount of time it takes for speech to exit the speaker’s mouth and reach the listener’s ear. Latency sounds like an echo.
There are 3 types of delay commonly found in today’s VoIP networks;
1. Propagation Delay: Light travels through a vacuum at a speed of 300,000km per second, and electrons travel through copper or fibre at approximately 200,000km per second. A fibre network stretching halfway around the world (21,000km) induces a one-way delay of about 70 milliseconds (70 ms). Although this delay is almost imperceptible to the human ear, propagation delays in conjunction with handling delays can cause noticeable speech degradation.
2. Handling Delay: Devices that forward the frame through the network cause handling delay. Handling delays can impact traditional phone networks, but these delays are a larger issue in packetised environments.
3. Queuing Delay: When packets are held in a queue because of congestion on an outbound interface, the result is queuing delay. Queuing delay occurs when more packets are sent out than the interface can handle at a given interval.
The Solution: Prioritise
Prioritising VoIP traffic over the network yields latency and jitter improvements. Policy based network management, bandwidth reservation, Type of Service, Class of Service, and Multi-Protocol Label Switching (MPLS) are all widely used techniques for prioritising VoIP traffic. A quality VoIP router can solve many of these issues and will result in business quality Business VoIP Phone Service.
5. The Problem: Internal Network Improperly Configured
VoIP is less than 10-years old. Many companies do not consider the higher quality demands of VoIP communications. If your company decides to route both voice and data over the same network without properly configuring your network for VoIP traffic, you can expect to have call quality issues.
The Solution: Network Configuration
This is one of the easiest and least expensive problems to correct. A Business VoIP capable router that is properly configured will generally solve the problem.
Contact us for more information if you are considering implementing VoIP but are not sure how your network or Internet connection will handle it.