Paessler PRTG

The IP Sniffer – PRTG


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    PRTG filters traffic by IP addresses

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    PRTG displays IP data on custom dashboards
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    PRTG sounds the alarm in the event of IP anomalies

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    PRTG facilitates IP packet analysis







IP sniffing: One PRTG sensor for immediate results


 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.

View video (3:26 min.)

packet sniffer sensor

The Packet Sniffer sensor monitors your traffic, then filters it by IP address, protocol, and connection. It also analyzes the headers of incoming and outgoing data packets. All this data is presented graphically on a customizable PRTG dashboard, which is perfect for keeping a constant eye on the status of your network.


The first 100 sensors are free – including the IP sniffing sensor

PRTG at a glance

PRTG at a glance

PRTG monitors your entire network (local and wireless), including its hardware, apps, and virtual machines. It comes with 250 preconfigured sensors which are quick and easy to set up. Depending on your license, PRTG lets you create thousands – or even tens of thousands – of sensors.

100 free sensors

100 free sensors

The first 100 sensors are free and never expire. The basic version of PRTG comes with all the software’s features, including dashboards, reports, and the alarm. If you’re looking for a tool to filter your traffic by IP address, then give the free version of PRTG a try.


Keep a constant eye on your network – 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



IP sniffers vs. network monitoring tools


IP sniffers

There are a number of IP sniffers on the market which you can use to take a look at individual IP packets. These tools will provide you with detailed information on the data that is carried in each respective packet (packet capture). Another function of IP sniffers is to inspect any suspicious data traffic in the network.

Network monitoring tools

PRTG is network monitoring software. It lets you monitor your entire network traffic. Among other things, you can keep an eye on your bandwidth and filter your network traffic by type, protocol, origin, and destination. PRTG comes with a built-in alarm that immediately notifies you in the event of a problem.

IP packet analysis

Looking for a way to analyze your IP packets? Many system administrators use PRTG before deploying IP sniffers, for PRTG analyzes packet headers to give you a better idea of which traffic deserves closer attention. You can then put the IP sniffer to work in more of a targeted fashion. With PRTG, you’ll save a great deal of time by narrowing data down before running analyses.


Three more PRTG sensors that make monitoring a cinch


CPU sensors

CPU sensors keep an eye on the CPUs of your servers, routers, and switches. They show you the capacity of your processors for a specific period of time or an individual process. If you notice a load increasing over time, you can take action at once. Find out how to set up CPU monitoring here.


Flow sensors

PRTG monitors all the major Flow protocols. As with the Packet Sniffer Sensor, you can break down and take a closer look at your traffic. The NetFlow protocol is mostly used by Cisco devices. Flow sensors are included in every version of PRTG. No upgrade is required.


HTTP sensors

Our HTTP sensors are designed to monitor your website. Processes, load times, worldwide availability...PRTG gives you total control. Website monitoring is especially important for websites with high levels of customer traffic (such as those with online stores), as well as for educational institutions.


Sniff IPs once or monitor continuously?

One-time sniff

One-time sniff

Many administrators use IP sniffers as an analyzer to resolve a specific problem. Example: getting to the root of a short-term spike in traffic.

Continuous monitoring

Continuous monitoring

PRTG keeps a constant eye on your entire network. It uses historical data to recognize long-term trends. As a result, PRTG helps you plan and develop your network infrastructure.

 iAn IP address (internet protocol address) is a numerical representation that uniquely identifies a specific interface on the network. IP addresses are binary numbers but are typically expressed in decimal form (IPv4) or hexadecimal form (IPv6) to make reading and using them easier for humans.
Read more


stephan linke

“Hi Stephan, as a system administrator, why should I monitor my network IP addresses via sniffing?”

“The Packet Sniffer Sensor provides a continuous overview of your network. If, for example, email traffic from a particular IP address increases or P2P file sharing occurs over the company network, you will be notified immediately. IP sniffing is therefore a good way to improve the security of your network.”

Stephan Linke, technical support at Paessler AG


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


PRTG is worth it: You’ll optimize your entire IT!

The costs for a one-year PRTG license usually pay for themselves within a few weeks.



An introduction to network monitoring with PRTG


FAQ: IP sniffers

How does an IP sniffer work?

A sniffer is a tool or program that inspects data traffic. Incoming and outgoing data traffic is “sniffed” as it passes through network interfaces. Sniffers log data packets and use IP addresses to identify senders and recipients.

How do I use an IP sniffer?

If you have a critical problem – such as unusually high network traffic or trouble transmitting data – an IP sniffer will help you uncover the cause. IP sniffers can even be used to sniff the traffic itself (i.e. individual data packets). The PRTG Packet Sniffer Sensor monitors traffic around the clock, including the distribution of traffic across devices, applications, and IP addresses.

What is an IP scanner?

The term “IP scanner” is often used synonymously with “IP sniffer.” But sometimes a sniffer tool will also be referred to as an IP scanner. IP scanners are mostly used to scan systems such as Microsoft, Mac, or Linux. PRTG also scans your network but is referred to as network monitoring software because it provides for continuous monitoring.

How do I install the PRTG IP sniffer?

When you execute PRTG for the first time, the auto-discovery feature will be launched automatically. Simply enter a range of IP addresses. PRTG will add all the devices within this range to your monitoring environment. You will then create the Packet Sniffer Sensor separately on the server whose traffic you wish to monitor, or via the monitoring port of your switch if you wish to include all traffic in your monitoring.


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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Looking to monitor traffic? Find out how PRTG can help!




Packet sniffing

Flow (IPFIX, NetFlow, sFlow, jFlow)




Easy to complex (depending on filter rules used)

Can be complex (the switch must be configured, for example)

Filters traffic





Shows toplist graphs (Top Talkers, Top Connections, Top Protocols)





Filters bandwidth usage by IP address





Filters bandwidth usage by MAC address





Filters bandwidth usage by physical network port





Monitors network parameters other than bandwidth usage





CPU load on the machine running PRTG



Higher, depends on the amount of traffic

Higher, depends on the amount of traffic

Excess bandwidth usage of monitoring



None (except when monitoring switch ports are used)

Depends on the traffic


Create innovative solutions with Paessler’s partners

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


With ScriptRunner, Paessler integrates a powerful event automation platform into PRTG Network Monitor.

Read more


Siemon and Paessler bring together intelligent building technology and advanced monitoring and make your vision of intelligent buildings and data centers become reality.

Read more


UVexplorer integrates tightly with PRTG to bring fast and accurate network discovery, detailed device inventory, and automatic network mapping to the PRTG platform.

Read more


Want to learn more about IP monitoring? Please do!

IPFIX monitoring

The IPFIX protocol is an advanced version of the NetFlow protocol. PRTG comes with two IPFIX sensors. Both of these sensors sort and filter the traffic in your network.

Learn more

VoIP monitoring

Tired of dropped calls and video conferences? If so, then PRTG QoS monitoring is for you. Our preconfigured sensors help you monitor the quality of your VoIP.

Learn more

IP SLA monitoring

Cisco devices with the IP SLA feature gather information on VoIP-related parameters such as latency, jitter, and packet loss. With the PRTG IP SLA Sensor, you can read these values and integrate them into your monitoring environment.

Learn more

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



quote steffen ille

“The greatest advantage of PRTG? You get to rest easy.“

Steffen Ille, Bauhaus-University of Weimar, Germany


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 (February 14th, 2024)


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


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Up to 100 sensors for free (Price List)

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

Supported Vendors & Applications

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