VoIP Monitoring Tools

VoIP telephony is becoming increasingly popular both for private and business communications. However, VoIP related network traffic is especially sensitive to even slight problems in connectivity. The sound quality of VoIP calls drops dramatically in the case of packet delay, jitter and packet loss. You should therefore closely monitor the quality of VoIP connections.

PRTG Network Monitor offers two comprehensive VoIP monitoring tools

• IP-SLA sensor
• QoS Sensor

IP-SLA Sensor: The VoIP Monitoring Tools for Cisco Routers

Cisco's IOS based routers have a built VoIP monitoring feature called IP-SLA Monitoring which can - among other things - monitor the Quality of Service (QoS) between two Cisco switches: Cisco IOS based routers collect network information in real time: response time, one-way network latency, VoIP jitter, packet loss monitoring, packet delay, voice quality measurement etc. You can use PRTG to monitor the resulting measurements.

IP SLA monitoring is only available in the more expensive boxes from Cisco. If you don't have IP SLA capable routers/switches you can still get similar information with PRTG's QoS monitoring functionality which does not require any special hardware - just two PCs running Windows. The QoS sensor measures the quality of a network connection by looking at quality of service parameters like jitter, packet loss, duplicate packets, and other readings.

The QoS sensor works by sending UDP packets between two remote probes. This is the perfect VoIP monitoring tool, enabling you to find network issues that can affect VoIP sound quality.

PRTG VoIP Monitoring Tools

The PRTG VoIP monitoring manager is available in two editions. For basic, free bandwidth tracking, availability and VoIP monitoring, the Freeware Edition may be downloaded and used for personal and commercial use completely free of charge. You can even use the freeware as a free IP SLA Monitor. For more advanced needs, licenses for the Commercial Editions start at $400 / €300.