Paessler PRTG

Use PRTG VPN monitoring to safely transfer data in a virtual network


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    Monitor VPN connections
    and the local network

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    Measure traffic, load,
    and the number of users

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    Identify connection problems
    and suspicious traffic






VPN Monitoring: Professional monitoring of virtual private networks


 i How PRTG defines sensors

In PRTG, “sensors” are the basic monitoring elements. One sensor usually monitors one measured value in your network, e.g. the traffic of a switch port, the CPU load of a server, the free space of a disk drive. On average you need about 5-10 sensors per device or one sensor per switch port.

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VPNs provide secure access to the company network

VPNs provide secure access to the company network

With VPNs, employees who do not work within the company network (such as those working from a home office) are nevertheless able to access company applications and collective resources securely. Branch offices can also connect, and mobile workers are able to effectively work with clients. With the encrypted transportation of sensitive company data come strict requirements regarding security and connection stability. To meet these requirements, PRTG offers VPN monitoring.

Sensors promptly sound the alarm

Sensors promptly sound the alarm

VPN monitoring sensors gather information regarding the VPN connection, such as which users used a VPN to connect (or are presently connected) to the company network and at what time, the type of connection, and the volume of data that is transferred over a certain period. They record connection problems and send alerts to administrators in the event of errors or numerous failed connection attempts. PRTG lets you counter attacks by identifying irregularities in the network. You’ll create transparency with regard to the resources that are being used, which in turn will help with licensing and the purchasing of supplies.

Monitor private networks

Monitor private networks

PRTG provides you with a quick and comprehensive overview of your virtual private network. You'll gain valuable insight on traffic, connections, and users, and receive decision-making support for service management and upgrades for your IT equipment, if needed. With PRTG, your VPN networks will boast an optimal system status, as well as application security and connection stability.

PRTG lets everyone work with peace of mind – both in and out of the office.

 iVPN stands for Virtual Private Network. It is a method by which two end-points create a single, private connection, or tunnel, while using a larger network infrastructure such as the internet or wide area network. When established, a VPN acts like a direct connection to a private network.
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An introduction to VPN monitoring with PRTG



Quick and easy setup of PRTG VPN monitoring



 i SNMP stands for Simple Network Management Protocol. Its usefulness in network administration comes from the fact that it allows information to be collected about network-connected devices in a standardized way across a large variety of hardware and software types. SNMP is a protocol for management information transfer in networks, for use in LANs especially, depending on the chosen version.
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How VPN monitoring works

How VPN monitoring works

To make a VPN partner’s connection to a company network secure, VPNs use SSL-encrypted remote access with the Internet as a path. This path ends at a VPN gateway, or the dial-in node of the company network. Beyond this point, the VPN partner acts as a regular network client, accessing applications and data and using collaborative tools like all the others.

Along with VPNs for connecting branches to the network (end-to-site VPN), there are also VPNs for connecting two networks (site-to-site VPN) and for the direct connection between VPN partners (end-to-end VPN). PRTG sensors check virtual networks for availability, VPN connection types, load, and errors, as well as according to various parameters such as connected user accounts and transferred data volumes and packets.

PRTG offers several sensors for VPN monitoring

PRTG offers several sensors for VPN monitoring

PRTG uses the Simple Network Management Protocol (SNMP) for its VPN monitoring. SNMP is the easiest way to monitor a network, as network and CPU loads are kept to a minimum. PRTG comes with a number of default sensors that use SNMP to monitor the VPN traffic, users, and connections of your Cisco ASA. It also lets you keep a constant eye on the VPN traffic on your SonicWall.

Automatic alerts

Automatic alerts

If you ever need more data, or would like to use the firewalls and security appliances of other manufacturers, you can do so with the PRTG user-defined SNMP sensors. Manufacturers such as Juniper and Fortigate provide MIB files which you can incorporate into PRTG with the SNMP Library Sensor, for example, allowing you to monitor the corresponding VPNs. As a result, you are not only restricted to the data that is read by PRTG by default.


3 good reasons to choose PRTG as your VPN monitoring tool

Secure data traffic

Continuous monitoring minimizes the risk of security loopholes. And proactive troubleshooting reduces blocks in the flow of data traffic between VPN partners and the company network. With PRTG, you’ll quickly get to the root of any problem.

Gain an overview

The dashboard offers easy-to-read details on traffic, users, applications, and the other parameters of your VPN connections. Which users are online and offline? Which applications are needed? And how often? You can count on PRTG to always let you know.

Set up intelligent alarms

Should VPN problems, suspicious traffic, or overloads arise, you’ll be informed immediately by the instrument of your choice (SMS, email, or push notification). The PRTG alarm function can be customized with your own individual threshold values.


Quickly see if your virtual private network is up and running – even while on the go

Set up PRTG in minutes and use it on almost any mobile device.


PRTG comes with all the features you need, plus more your IT infrastructure won't want to live without.



PRTG monitors these vendors and applications in one view!


vendors vm ware



quote steve coppin

“I particularly like having breakfast at home and just surveying my domain, and understanding what's working and what isn't.”

Steve Coppin, Oxford University


VPN monitoring sensors

The following sensors can be used for VPN monitoring with PRTG:


Monitors the traffic of an IPsec VPN connection on a Cisco ASA using SNMP and shows the incoming and outgoing traffic.

SNMP Cisco ASA VPN Traffic Sensor

SNMP SonicWall VPN Traffic

The SNMP SonicWall VPN Traffic sensor monitors the traffic of an Ipsec VPN on a Dell SonicWall NSA via SNMP. It can show:

  • Number of encrypted and decrypted packets per second
  • Bytes of encrypted and decrypted transmissions per second
  • Number of ingoing and outgoing fragmented packets per second

SNMP Library

The SNMP Library sensor uses a MIB library file to create sensors that monitor a device via SNMP and provides custom monitoring beyond the standard SNMP sensors of PRTG.


Trusted by 500,000 users and recognized
by industry analysts as a leader

“Fantastic network and infrastructure monitoring solution that is easy to deploy and easier still to use. Simply the best available.”

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“Software is absolutely perfect, Support is superior. Meets all needs and requirements, this is a must have solution if you are needing any form of monitoring.”

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“The tool excels at its primary focus of being a unified infrastructure management and network monitoring service.”

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We asked: would you recommend PRTG?
Over 95% of our customers say yes!


Paessler AG 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.


Recommend PRTG


Data gathered by PRTG during VPN monitoring

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    and outgoing traffic

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    The type and speed
    of data packets

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    Connected users
    and duration of
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    Connection types and active connections (Email, IPsec, L2L, LB, SVC)

PRTG is a vital tool for getting your IT into tip-top shape!

The costs for a one-year PRTG license pay for themselves in an average of only a few weeks.
License costs vary according to the size of your network.

PRTG makes your network more reliable

PRTG improves the reliability of your network

PRTG saves network management costs

PRTG saves network management costs

PRTG saves time spent on network management

PRTG saves time spent on network management

also of interest

Also of interest:


Active Directory Auditing: PRTG offers integrated complete Active Directory Monitoring in real time. Find out more about Active Directory Monitoring here.

Ping Monitoring: PRTG uses ping to check the availability of all your network devices. If the ping fails, you will be notified immediately.

Is your line choppy? Do your video calls keep getting dropped? If so, then you have a problem with your quality of service. PRTG lets you set up easy and effective QoS monitoring and monitor values such as latency and jitter. PRTG also comes with  IP SLA sensors for SNMP devices.


Create innovative solutions with Paessler’s partners

Partnering with innovative vendors, Paessler unleashes synergies to create
new and additional benefits for joined customers.

IP Fabric

Combining the broad monitoring feature set of PRTG with IP Fabric’s automated network assurance creates a new level of network visibility and reliability.

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Rhebo and PRTG offer a comprehensive monitoring solution for IT and OT environments: from condition monitoring through to anomaly and threat detection.

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“Easy to implement and configure with good technical support.”

R. v. S., ICT Manager at Heinen & Hopman Eng BV


PRTG the multi-tool

PRTG: The multi-tool for sysadmins

Adapt PRTG individually and dynamically to your needs and rely on a strong API:

  • HTTP API: Access monitoring data and manipulate monitoring objects via HTTP requests
  • Custom sensors: Create your own PRTG sensors for customized monitoring
  • Custom notifications: Create your own notifications and send action triggers to external systems
  • REST Custom sensor: Monitor almost everything that provides data in XML or JSON format


Still not convinced?



More than 500,000 sysadmins love PRTG

Paessler PRTG is used by companies of all sizes. Sysadmins love PRTG because it makes their job a whole lot easier.

Still not convinced?


Monitor your entire IT infrastructure

Bandwidth, servers, virtual environments, websites, VoIP services – PRTG keeps an eye on your entire network.



Try Paessler PRTG for free

Everyone has different monitoring needs. That’s why we let you try PRTG for free. Start now with your trial.




Network Monitoring Software - Version (April 10th, 2024)


Download for Windows and cloud-based version PRTG Hosted Monitor available


English, German, Spanish, French, Portuguese, Dutch, Russian, Japanese, and Simplified Chinese


Up to 100 sensors for free (Price List)

Unified Monitoring

Network devices, bandwidth, servers, applications, virtual environments, remote systems, IoT, and more

Supported Vendors & Applications

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