Custom alerts and data visualization let you quickly identify and prevent quality of service issues.
Paessler PRTG’s free VoIP monitoring software is the caretaker for your digital communications, quietly watching for potential issues with VoIP call quality and reliability. Know when to act before an issue arises.
Diagnose network issues by continuously tracking the quality of your VoIP system. Show VoIP jitter, as well as packet loss and other key performance metrics in real time. Visualize monitoring data in clear graphs and customizable dashboards to identify problems more easily. Gain the overview you need to troubleshoot issues with voice quality and other VoIP services.
Live traffic data graph in PRTG
Device tree view of the complete monitoring setup
Custom PRTG dashboard for keeping an eye on the entire IT infrastructure
Live traffic data graph in PRTG
Device tree view of the complete monitoring setup
Real-time notifications mean faster troubleshooting so that you can act before more serious issues occur.
“All-around winning
network monitor”
“The real beauty of PRTG is the endless possibilities it offers”
“PRTG Network Monitor
is very hard to beat”
More than 500,000 end users trust PRTG’s user-friendly interface. It’s easy to install, manage, and navigate, even if you have limited technical expertise. All your important data is available in a central visual dashboard, as well as on a variety of mobile devices.
Best of all, PRTG doesn’t need any special hardware or agents for QoS monitoring, so it’s cost-effective for any business size.
You can try the full, unlimited version of PRTG for 30 days free of charge. After this time, you’ll continue to get access to 100 sensors for as long as you like.
PRTG is an industry-leading, Windows-based on-premises or cloud-based network performance monitoring solution that is designed to grow with your needs. Start with free VoIP monitoring and all the free network monitoring benefits that come with PRTG, and upgrade when you’re ready.
You can have peace of mind in the office, in the car, at home, or on the beach. PRTG lets you remotely monitor your VoIP system, so quality and performance are maintained no matter where you are.
Access the central dashboard from your desktop or on our PRTG apps for iOS and Android, and be alerted of any IT infrastructure issue via push notification.
PRTG comes with more than 250 native sensor types for monitoring your entire on-premises, cloud, and hybrid cloud environment out of the box. Check out some examples below!
The QoS (Quality of Service) Round Trip sensor monitors parameters regarding the quality of a network connection between two probes. It can show the following:
The Cisco IP SLA sensor monitors Voice over IP (VoIP) network parameters using IP service level agreements (SLA) from Cisco. It can show the following:
The Ping Jitter sensor sends a series of Internet Control Message Protocol (ICMP) echo requests ("pings") to a URI to determine the statistical jitter. It can show the following:
See the PRTG Manual for a list of all available sensor types.
Real-time notifications mean faster troubleshooting so that you can act before more serious issues occur.
Set up PRTG in minutes and use it on almost any mobile device.
As a member of the Cisco Partner Program, Paessler is one of the market leaders that enhances the Cisco technology portfolio with products that are proven to easily integrate with Cisco devices.
What does this mean for you?
Partnering with innovative IT vendors, Paessler unleashes synergies to create
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Custom alerts and data visualization let you quickly identify and prevent quality of service issues.
Network Monitoring Software – Version 25.1.104.1946 (March 18th, 2025)
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Quality, reliable business communications are crucial to stay in operation. VoIP (Voice over Internet Protocol) monitoring performs several functions necessary to ensure business continuity:
VoIP monitoring tools report on issues that impact your voice communications. Key call quality metrics include latency, jitter, and packet loss.
In VoIP terminology, a “voice packet” is a unit of data that carries all the information about your voice. When you speak, your voice is turned into an encoded, compressed snippet of data and then broken down into smaller pieces that are easier to transmit. These pieces are called “packets”.
Packet loss means what it sounds like. Somehow, one or many packets of data have been lost in transmission. If you’ve ever been in a VoIP call that cuts in and out or a video call where someone freezes in the middle, you’ve experienced packet loss.
When you ask a question and wait for the other person to answer, the space in between is latency. In that space are a lot of “time” measurements:
If any of these areas have high latency, it will significantly affect the quality of your VoIP call.
If latency is the time it takes to process a packet, jitter is how inconsistent the time on delivery is. Ideally, there’s no delay, meaning low jitter. Congested networks, inconsistent network quality, and improper queuing, among other network issues, can cause high jitter and quality of service issues.
The Mean Opinion Score, or MOS, is a metric that measures the quality of voice calls. The MOS is your VoIP report card. Individuals grade the quality of the call when it’s finished, and then those grades are averaged. The average score becomes the MOS.
A comprehensive VoIP monitoring tool should provide the following:
In PRTG, “sensors” are the basic monitoring elements. One sensor usually monitors one measured value in your network, for example the traffic of a switch port, the CPU load of a server, or the free space on a disk drive. On average, you need about 5-10 sensors per device or one sensor per switch port.
Paessler conducted trials in over 600 IT departments worldwide to tune its network monitoring software closer to the needs of sysadmins. The result of the survey: over 95% of the participants would recommend PRTG – or already have.
Paessler PRTG is used by companies of all sizes. Sysadmins love PRTG because it makes their job a whole lot easier.
Bandwidth, servers, virtual environments, websites, VoIP services – PRTG keeps an eye on your entire network.
Everyone has different monitoring needs. That’s why we let you try PRTG for free.
