QoS Monitoring

QoS monitoring (Quality of Service) is essential in order to ensure good VoIP quality and for quick, effective troubleshooting. PRTG Network Monitor is a VoIP monitoring software offering two types of sensors for QoS monitoring: the QoS sensor and the IP SLA sensor.

For QoS monitoring, PRTG includes a QoS sensor which is used to monitor the quality of a network connection by looking at "quality of service" parameters like VoIP jitter, packet loss, packet delay variation, and other readings.

Slight variations of these parameters usually have only little effect on TCP-based services (e.g. HTTP, SMTP, etc.). But for UDP-based services like VoIP a steady stream of data packets is crucial. The sound quality of a VoIP call drops dramatically when UDP packets are not received in a timely fashion, in the case of packet loss or if packets are reordered. The QoS monitor measures the following network connectivity parameters:

• Jitter in ms according to RFC 3550
• Packet delay variation (PDV) in ms according to RFC 3393
• Lost packets in %
• Reordered packets in %
• Duplicated packets in %

PRTG Network Monitor offers far more than QoS monitoring. From a simple ping test to complex bandwidth and availability monitoring, our network diagnostic tools help you to keep control of your network.

PRTG Qos Monitor is available as fully functional 30-day trial license and Freeware Edition, which is completely free for personal and commercial use. The Commercial Editions are required to monitor more than ten sensors, with licenses starting at just $400 / €300.

The QoS monitor takes measurements by sending UDP packets between two remote probes. This means that you can test any network connection in your network by simply placing a remote probe on (or near) each "end" of the connection and measuring the connection quality between them. If the QoS monitor detects a problem, the network administrator is notified immediately and can react quickly and effectively to any issues. Thus PRTG is the perfect tool for QoS monitoring and VoIP network monitoring as it finds network issues that can affect VoIP sound quality.

QoS monitoring is not only essential for VoIP, but also for other network services such as video streaming.

The second possibility for QoS monitoring with PRTG is IP SLA monitoring, which is included in the Cisco IOS Software. Either of the two methods works fine for QoS monitoring.