How to Look at Network Traffic: Essential Tools and Methods for Real-Time Analysis

In this complete guide, we’ll cover the tools, methods, and best practices that you need to monitor network traffic in real time, analyze network performance, and keep all your network devices operating at maximum efficiency.

Why You Should Monitor Network Traffic

Every day, terabytes of data flows through your network infrastructure. DNS queries, TCP and UDP connections, web requests, and email traffic are just a few examples of the network activity that your routers, firewalls, and switches are responsible for processing every second. By monitoring network traffic, you can identify potential problems before they become outages.

Network activity monitoring allows you to see which parts of your infrastructure may be bottlenecking network traffic, detect unusual behavior that could indicate malware or other cybersecurity threats, and optimize your network performance based on historical traffic patterns. Network monitoring isn’t just about troubleshooting - it’s about preventing issues in the first place.

Understanding Network Traffic

Before we dive into tools and methods, it’s important to understand the basics of what network traffic actually is. Network traffic refers to all of the data packets moving through your network infrastructure. This includes:

▪️ Protocol-based traffic
TCP, UDP, ICMP, and other network protocols that govern how data is transmitted and received through your network

▪️ Application traffic
Data from applications, web browsers, email clients, and business software

▪️Device communication
Network communication between devices like routers, switches, firewalls, and servers

▪️ Internet traffic
Connections to and from the internet

Analyzing each of these types of traffic provides valuable metrics and data about the health and performance of your network infrastructure. By collecting and visualizing IP addresses, bandwidth utilization, and network connections, you can gain deep visibility into your network operations.

Best Practices: How to Monitor Network Traffic

1. SNMP Monitoring

The Simple Network Management Protocol (SNMP) is one of the most common network monitoring methods. SNMP allows you to gather network data from multiple devices (Cisco routers, switches, and firewalls, for example).

If you’re monitoring bandwidth usage and device performance across your entire network, SNMP is a great option.

SNMP reports network performance metrics in real-time, making it an excellent choice for bandwidth monitoring and troubleshooting network bottlenecks before they lead to performance issues. The SNMP Traffic sensor and Bandwidth sensors from PRTG are easy to use and simplify SNMP monitoring.

Want to learn more about monitoring protocols and how they differ? Read the guide on NetFlow vs SNMP for IT monitoring.

2. NetFlow and Flow-Based Analysis

NetFlow is a Cisco protocol that provides traffic analysis for your network. NetFlow monitoring works by gathering information on traffic flows.

It gives you visibility into the IP addresses that are using the most bandwidth, what apps are using the most traffic, and how data flows through your network topology.

Flow-based monitoring protocols are compatible with different devices and provide a more holistic view than simple bandwidth monitoring. PRTG has support for several flow protocols with sensors like the NetFlow v9 sensor and IPFIX sensor.

3. Packet Sniffing

Packet sniffer tools capture and analyze individual data packets as they travel through your network. This method provides the deepest level of network traffic analysis, allowing you to examine the actual contents of network connections.

While tools like Wireshark are powerful open-source options for packet-level analysis, they can be complex and generate massive amounts of data. PRTG's Packet Sniffer sensor offers a more streamlined approach to packet sniffing. For practical implementation tips, read this article about monitoring network traffic with SNMP and packet sniffing.

4. Built-in Operating System Tools

Both Windows and Linux offer built-in functionality for basic network monitoring. Windows users can leverage Task Manager and Resource Monitor, while Linux administrators have access to tools like netstat, tcpdump, and iftop. Microsoft also provides Performance Monitor for more detailed metrics.

These native tools are user-friendly and require no additional installation, making them perfect for quick checks and basic troubleshooting.

Ready to Take Control of Your Network?

Network traffic management is easy with PRTG Network Monitor. It offers full network traffic monitoring including real-time dashboards, instant alerts, and detailed graphs so you can easily visualize your network. Track your bandwidth consumption, NetFlow, and SNMP network traffic all in one platform. PRTG’s intuitive platform makes network traffic monitoring easy.

👉 Download your free trial of PRTG and start monitoring your network traffic in minutes, not hours.

Essential Features of Network Monitoring Tools

When choosing network monitoring tools for your network infrastructure, there are some key features you should look for:

📌 Live monitoring: This includes real-time monitoring with dashboards that show live network activity and bandwidth consumption.

📌Historical monitoring: Network monitoring tools should also include long-term storage of historical network data. This allows for analysis of data trends over time, such as capacity planning and troubleshooting.

📌Customizable alerts: Automated notifications of when network performance is downgraded or abnormal activity is occurring can help you catch network issues early.

📌Multi-protocol support: SNMP, NetFlow, packet sniffing, and other monitoring types should all be supported by your network monitoring tool.

📌User-friendly dashboards: Graphs and visualizations should be clear and easy to understand so that complex data is accessible to users.

📌Authentication and security: Features that will help you protect your network monitoring infrastructure from cybersecurity threats are a must.

📌Automation: Automating responses to common issues will help reduce manual intervention and network management overhead.

Network Traffic Monitoring Use Cases and Best Practices

Network Performance Troubleshooting

Got complaints about slow performance or a bad application experience? Monitor your network traffic to quickly determine the cause. Look for bandwidth usage patterns, check for congestion at critical devices like switches and routers, and review traffic flows.

Bandwidth Optimization

To optimize your bandwidth, you need to know how it is being used. Network traffic monitoring can help you discover where the top traffic hogs are located - whether it’s specific applications, users, or other areas. For example, you might learn that non-business apps are consuming bandwidth during office hours, or that your Wi-Fi network needs additional capacity in certain areas.

For more tips and best practices on bandwidth monitoring and management, read our complete guide to what is bandwidth usage and how to monitor it.

Security and Threat Detection

Analyzing network traffic is essential to a strong cybersecurity strategy. It’s a good way to identify suspicious activity that might indicate a malware infection or data breach. For example, if your monitoring tools alert you to strange traffic patterns, connections to unusual external IP addresses, or large amounts of data leaving your network, that’s worth investigating. Better yet, if you use real-time monitoring, you can spot these security issues quickly and stop them before they do too much damage.

Capacity Planning

You can use historical network monitoring data to make informed decisions about your capacity planning. Use the metrics your monitoring tools gather to understand traffic trends over weeks, months, or even years. This data will help you know when to upgrade your routers, add more bandwidth, or scale out your network resources.

Best Practices for Network Traffic Monitoring

🎯 Establish baselines: Document the normal performance levels in your network so that you can more easily spot anomalies and problems

🎯 Monitor all critical devices: In addition to endpoints, don’t forget routers, firewalls, switches, and Windows/Linux servers

🎯 Set meaningful thresholds: Configure alerts that will alert you to actual problems, rather than bombarding you with false positives

🎯 Use multiple methods: Use SNMP, NetFlow, and packet sniffing to get comprehensive visibility

🎯 Regular reviews: Set aside time to review historical data and identify long-term trends

🎯 Document your topology: Keep a current map of your network infrastructure for troubleshooting

Start Monitoring Your Network Traffic Today

Monitoring network traffic is one of the best practices when it comes to maintaining a healthy and high-performing network infrastructure. The key is to use the right network traffic monitoring methods such as SNMP , NetFlow, and packet sniffing, in conjunction with a powerful network monitoring tool that provides full visibility into your network activity.

Ideally, the tool you choose to monitor network traffic should include both real-time network monitoring to catch issues early on, as well as historical network data collection for ongoing optimization efforts. This type of functionality is relevant to businesses of all sizes and use cases. From small office networks with a single router to enterprise networks with multiple routers, firewalls, and network devices.

PRTG Network Monitor has all the features you need in one easy-to-use platform. It supports SNMP, NetFlow, packet sniffing, and much more, to give you full visibility into your network activity and, in turn, allow you to monitor network traffic effectively. In addition, its intuitive dashboards and graphs simplify the interpretation of complex data, while the powerful automation options make it possible to automate tasks and respond to issues even faster.

👉 Start your free PRTG trial today and discover how easy network traffic monitoring can be. No credit card required - just download, install, and start monitoring in minutes.

FAQ

What's the difference between bandwidth monitoring and network traffic monitoring?

Bandwidth monitoring is concerned solely with measuring data transfer rates over network connections. Network traffic monitoring provides a more comprehensive view, including insight into which applications, IP addresses, and protocols are generating network traffic.

Can I monitor network traffic on both Windows and Linux systems?

Yes, modern network monitoring solutions support both Windows and Linux platforms. In addition, many tools have cross-platform capabilities, allowing you to monitor your entire mixed-platform network infrastructure from a single dashboard.

Do I need expensive tools to monitor network traffic?

Open-source tools like Wireshark are available, but effective network monitoring often requires commercial solutions with features such as real-time dashboards, historical data storage, automated alerting, and support for multiple protocols (SNMP, NetFlow, etc.). Many paid products offer free trials, allowing you to test their features before purchasing.

How does network traffic monitoring help with cybersecurity?

Network traffic monitoring can detect malware, intrusions, and data exfiltration attempts by identifying unusual traffic patterns, unexpected connections, and abnormal data volumes. By monitoring in real-time, you can respond to security incidents quickly, before they have a chance to do too much damage.