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Voip QOS Facts and Recommendations

VoIP QoS: Basic Facts and Recommendations on Adjustment


VoIP QoS (short for Quality of Service) is one of the most essential things that must be tested and configured to get the best quality of audio and video signal.

QoS Basics

Quality of Service is a pre-defined, qualitatively established level of service quality which is expected to be obtained from the communication network. In this regard, a Voice-over-IP system has its own set of specifications which should be controlled in order to make or receive a high quality call over the Internet.

These include:

Bandwidth. In terms of QoS bandwidth is one of the main factors, since it defines whether the call is held correctly or not. It goes without saying that with unlimited constant bandwidth a call can be conducted from end-to-end without problems. However, in case of an overwhelmed line, various issues may occur.

Delay. Although some delay can be normally taken with data communication/exchange, it can make the quality of call unbearable. Sure, all voice/video communication technologies imply some delay, yet it must be kept to a number that is as small as possible. Typically, QoS for optimum VoIP call defines end-to-end delay of less than 150ms.

Jitter. Jitter is referred to the amount of delay variation in call traffic. For example, in traffic with a constant delay at 100ms, no problems occur. However, if there is a short delay (5 ms, for instance) which is followed by a portion of long delay (e.g., more than 300ms), and the one more period of short delay, the voice receiving device may have hard time synchronizing all of the incoming traffic.

Loss. In case of loss of the voice packets the loss of audio occurs. As a rule small amounts of loss (less than 1%) during the communication course won't be noticed. However, in case of a large outflow, voice quality problems take place.
The aforementioned specifications are the most basic concepts QoS is attempting to accomplish in terms of VoIP.


What Is a VoIP QoS Test

Quality of Service tests enable you to obtain the quantitative data regarding your VoIP network efficiency. Once you have decided to conduct a test, you may use either a special program (these are often paid) or do this for free. To check your VoIP software at no charge we recommend you browse for a QoS bandwidth speed test online.

How to Adjust the VoIP QoS

If you are a separate user, there is a chance that your provider has already set auto QoS for your VoIP network. As a rule, these configurations favor voice over other types of data. However, if you have low level VoIP connection, you may try to troubleshoot the problem using one of the following methods:

Reboot your PC.
Update your software using your VoIP provider's official website.
Exit all other unnecessary programs and processes on your PC when making or receiving a call over the Internet (most VoIP services need a significant amount of bandwidth for quality calls).
Consider buying a top-notch set of headphones.