PRTG is a reliable port scanner that monitors data streams around the clock.
What is a port scanner?
A port scanner is a tool that checks the status of ports. It uses queries to determine whether a port is open, closed, or hidden.
- Open port: The computer accepts the query, responds, and asks what to do next.
- Closed port: The computer responds to the query and indicates that the port is in use and therefore unavailable.
- Hidden port: The computer provides no response to the query. The port may be hidden, filtered, locked, or blocked.
Some port scanners also scan open ports for additional information (such as the operating system in use), but this is not their primary purpose.
What is a port?
Ports are part of a network address (IP address). They ensure connections and data packets are assigned correctly and allow for the processing of services on the Internet. This may involve the transfer of data, the retrieval of an email, or the sending or receiving of a web page. Ports use a transport protocol to transmit information. Each port is assigned a non-random number. These numbers range from 0 to 65535, with 1 to 1023 used for Internet protocols.
What is a transport protocol?
A transport protocol – aka a “network protocol” – specifies how data is to be exchanged between the components in a network. In other words, it defines the way in which data is transmitted. The two most common protocols are the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP). PRTG can be used as a port scanner for both TCP and UDP.
Frequently used ports
Here are the most common ports and their uses:
- Ports 20 and 21: Transfer of files
- Port 25: Sending of emails
- Port 53: Assignment of names to an IP address (DNS)
- Port 80: Sending and receiving of web pages
- Port 110: Retrieval of emails
For the IP port scanner in PRTG, it doesn't matter which ports you use. The software detects all of them, which is why you can use it for all the ports in your company.
Why do I need a port scanner?
A port scanner like PRTG promptly scans for open ports, allowing you to check and control the security of your entire network. Open ports are dangerous as they make your network (and thus your entire IT system) vulnerable to attacks. Examples of attacks via open ports include the smuggling in of Trojans or the extraction of important company information. With the port scanner function in PRTG, you’ll benefit from the following advantages:
- Quick and reliable identification of weak spots
- Simple verification of the functionality of ports
- Constant updates thanks to precise monitoring with a customizable alert system
How does a port scanner work?
Transfer of data to a host
Port scanners work in a variety of ways. The simplest (and most common) way involves the uninterrupted transfer of data to a specific host. The port scanner notifies the system as soon as a data packet reaches an open port. Data packet types can also vary: TCP, UPD, ICMP, FIN, and ACK are just a few examples.
Vertical or horizontal scanning
Port scanners can scan both vertically and horizontally. With vertical scans, a single network address is scanned on multiple ports. Horizontal scans, on the other hand, test several network addresses on a specific port (e.g., port 80).
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PRTG helps you quickly check open ports
The port scanner function of PRTG lets you quickly and reliably scan for open ports. PRTG also comes with customizable notifications that alert you to open ports in real time – and thereby allow you to take appropriate security measures. During your monitoring, you’ll want to keep a close eye on the following ports:
A failed switch port or server port can affect the entire network. It is therefore vital that you know the status of these ports at all times. PRTG provides for the precise monitoring and scanning of your ports, allowing you to keep a constant eye on your entire system. What’s more, by regularly scanning your router ports, you’ll be able to optimize the use of your network capacity. In particular, PRTG lets you promptly take action before this capacity reaches its limit.
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PRTG makes your job easier
Our monitoring software frees you to focus on other tasks by promptly notifying you of potential issues.
PRTG gives you one central monitoring tool for your servers and entire network. Enjoy a quick overview of your whole infrastructure via our dashboard and app.
Getting started with PRTG is a breeze. Setting up or switching from another network monitoring tool is easy thanks to the auto-discovery and pre-configured device templates.
“The greatest advantage of PRTG? You get to rest easy.“
Steffen Ille, Bauhaus-University of Weimar, Germany
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The advantages of using
PRTG as your port scanner tool
With PRTG, you get an all-in-one tool for all your IT monitoring and port scanning needs. You can do away with individual monitoring solutions and enjoy the convenience of a single, comprehensive tool. Among other things, PRTG comes with:
Monitoring for all devices
Overview of open ports and security risks
Access to all the most common monitoring protocols
Solutions for small, medium, and large environments
Customizable thresholds and notifications
PRTG: The multi-tool for sysadminsAdapt 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?
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Bandwidth, servers, virtual environments, websites, VoIP services – PRTG keeps an eye on your entire network.
|Network Monitoring Software - Version 22.214.171.1244 (February 14th, 2024)
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