What is bandwidth monitoring and why is it important?
A bandwidth monitor tool provides real-time insights into usage across your network so you can proactively manage any bandwidth limits but most importantly identify bandwidth hogs on your network which could point to other issues such as a network intrusion.
Here’s our list of the best bandwidth monitoring tools:
- SolarWinds NetFlow Traffic Analyzer EDITOR’S CHOICE A bandwidth analysis package that communicates with network devices to extract traffic data with capabilities to manage multi-vendor networks. Runs on Windows Server. Start a 30-day free trial.
- Paessler PRTG Network Monitor (FREE TRIAL) A bundle of monitoring tools for networks, servers, and applications that includes traffic sampling sensors for traffic management. Installs on Windows Server. monitors.
- Datadog Network Performance Monitoring A cloud-based package that tracks network traffic patterns.
- ManageEngine Bandwidth Monitor The traffic analysis system uses a range of protocols to communicate with network devices from a number of manufacturers. Available for Windows Server and Linux.
- ntopng With a free community edition, this open-source network monitor uses nProbe to gather traffic flow information. Available for Windows, Linux, Unix, macOS, and RaspbianOS.
- Nagios A monitoring package for networks, servers, and applications that is available in free and paid versions. Runs on Linux or over a VM for Windows
- Progress WhatsUp Gold A network monitoring tool that installs on Windows and can be extended by a specialized Network Traffic Analysis module.
Why monitor internet bandwidth?
If you run a WAN with a lot of interaction between sites, if you integrate Cloud services into your IT infrastructure, or if your main business outlet is your website, your bandwidth monitoring needs to cover internet performance as well as network bandwidth utilization.
You no doubt have a service plan with an internet provider to connect your business together across the world and to communicate with suppliers and customers. You may have chosen a plan that does not provide you enough bandwidth. You will only discover that situation when you monitor bandwidth consumption on your internet connections.
Related post: The difference between Throughput and Bandwidth
Why use a network traffic monitor tool?
Your ISP promises to provide you with a reliable pipe to the Internet of a certain volume; your chosen network hardware install is designed to provide a particular level of service within your facility. Are you getting your expected bandwidth and availability, or is something failing to deliver? Is unexpected traffic consuming the bandwidth that you are getting?
Tools that monitor network traffic and bandwidth such as data usage meters can leverage various technologies. A host can observe all the data packets passing by a particular network interface (that is, packet capture). Most managed network devices – and hosts – support SNMP, and so they can be queried to get performance statistics.
Bandwidth monitoring focuses on the available capacity of network equipment and the amount of that capacity that is occupied by traffic. You can extend that visibility further by getting a breakdown of traffic volumes by application or by source and destination to spot where the real bandwidth hoggers are.
Network traffic statistics
You need to watch the bandwidth consumption of each link in your network, not just the overall bandwidth availability. One link can get congested, while others retain spare capacity. Adding on extra bandwidth to alleviate overloading on one link can cause extra throughput to get through and overload other links. That congested link may be hiding the under-provision of bandwidth in other areas of the network.
If your network devices support a traffic monitoring protocol like NetFlow or sFlow, they can publish traffic data to your monitoring tool. For more on these technologies, see Intro to traffic analysis in The best free NetFlow analyzers and collectors for Windows, and NetFlow vs sFlow: What’s the difference and which is better?
Network bandwidth monitoring tools
Which network bandwidth monitoring tools are right for you? There are several considerations when performing a network monitoring tools comparison. One factor is what monitoring technologies your installed hardware supports (eg, do they support SNMP? NetFlow? sFlow?). One is the size and complexity of your network; a simple tool that’s a great fit for a small office is completely inadequate for a large sophisticated network. Here we’ll look at the most popular and feature-rich free bandwidth monitoring software that can give you real-time data on your network and internet connection bandwidth utilization.
Monitoring tools that enable you to perform a network bandwidth test on-demand provide analytical functions. Troubleshooting bandwidth problems is impossible without the ability to collect and store network traffic.
Bandwidth monitoring requirements
You need a tool that can monitor your network for you while you are busy with other tasks. To get that level of service from your bandwidth monitor, make sure you choose a tool that is able to monitor router traffic levels approaching your full bandwidth availability and send you alerts. Reports that can be scheduled at all hours of the day will also help you keep watch on your bandwidth utilization 24/7.
Analytical features in tools help you plan your capacity requirements both to meet current demand, to account for trend traffic increases, and to provision for extra services when demanded.
If your chosen bandwidth tool can save collected traffic to a file, open files, and traffic data into a viewer, then you can begin to observe traffic patterns over time. Viewers that include filtering, sorting, and tagging capabilities will allow you to identify the sources of bandwidth capacity problems. Analytical tools that have sophisticated graphical representations for network data and comprehensive reporting formats will enable you to communicate problems and solutions to stakeholders in your organization and arrive at collaborative decisions.
The best bandwidth monitoring software
We have taken all of the above requirements into account and compiled recommendations on the software that you should consider when you are in the market for bandwidth monitoring software. There are many great monitors available at the moment, but you won’t have enough time to check all of them out. So, we wrote this guide in order to cut down the time you have to spend investigating new software for your enterprise.
Our methodology for selecting free bandwidth monitoring tools
We reviewed the available free bandwidth monitoring software and analyzed the options based on the following criteria:
- The capability to use traffic sampling protocols, such as NetFlow
- Time-series maps showing traffic volumes
- Traffic monitoring per link and point-to-point
- Alerts for devices reaching full capacity
- Traffic shaping measures
- Traffic analysis tools to aid capacity planning
- An option to upgrade to a comprehensive paid system
The SolarWinds NetFlow Traffic Analyzer offers full bandwidth monitoring and management features. The tool communicates with switches and routers through a series of communication protocols that were created by device manufacturers. These are NetFlow, J-Flow, sFlow, NetStream, and IPFIX. This range of capabilities enables the system to monitor a multi-vendor network.
- NetFlow, sFlow, J-Flow, IPFIX, and NetStream
- Traffic overviews
- Views per link
- Data per application or IP address
- Implement traffic shaping
As well as having the availability to use many different data sampling protocols, this service can operate with both IPv4 abd IPv6 addresses. IT is a flexible package that can adapt to all of the hardware used on your network.
The monitor can examine traffic flow rates on each link of your network. Taking this information in conjunction with switch and cable capacity will tell you when links get overloaded and where bottlenecks occur.
Once problems are noticed, you can use the traffic data segmentation features in the SolarWinds package to look for the main sources of all of that traffic.
See traffic by endpoint, by source IP address, and by application, and then you can try to mitigate the demand on the network or plan for greater capacity.
The NetFlow Traffic Analyzer includes a series of thresholds that you can activate. These trigger alerts when crossed, so you can assume that all is well with network unless you receive a notification by email or SMS.
If you implement queuing to prioritize specific applications, such as VoIP, you can take performance snapshots of application traffic at a switch, make adjustments to your queuing system, take another snapshot, and then compare the results.
The analysis features in this tool include a system called PerfStack, which allows you to specify conditions to monitor, get a time-series graph of that activity and then set up another graph of related activity and place that just below the first. With this tool you van view the synchronicity between different conditions on the network and work out how to improve traffic management.
The NetFlow Traffic Analyzer is part of a suite of tools produced by SolarWinds on a common platform, called Orion. This means that separate modules can combine and produce cross-over services. A good combination with the NetFlow Traffic Analyzer is the SolarWinds Network Performance Manager. The two modules can be bought in a bundle, called the Network Bandwidth Analyzer Pack.
- Network traffic overviews
- Switch activity reports
- Graphical representaitons
- Time-series graphs
- QoS management
- No cloud-based version
SolarWinds NetFlow Traffic Analyzer runs on Windows Server. You can appraise the package on a 30-day free trial.
SolarWinds NetFlow Traffic Analyzer is our top pick for a bandwidth monitoring tool because it combines switch and router querying with traffic shaping measures. The package is able to identify traffic by application and demonstrate which applications, users, or endpoints are the top traffic generators. You can work out which services and links on your network are overloaded and then do something about it. The system is also able to monitor activities on VMWare distributed virtual switches. The extensive features of this package offer real value for money.
Official Site: solarwinds.com/netflow-traffic-analyzer/registration
OS: Windows Server
The Paessler PRTG Network Monitor is a “batteries included” solution that monitors bandwidth utilization, the health of devices on your network, and more. The free version is limited to 100 sensors after the first month; since a sensor is an individual data stream, each device will typically require several sensors.
- Uses NetFlow and sFlow
- Packet capture function
- Live traffic flow graphics
- Identifies overloaded links
The PRTG Network Monitor runs on Windows. It uses SNMP, WMI, NetFlow, sFlow, and packet sniffing. Setting up the tool is a bit complex but a setup wizard and how-to video are provided.
Figure 11: Viewing top talkers, connections, protocols, and other utilization
- Free trial that converts to a limited freeware version after expiration
- Uses multiple protocols for monitoring allowing for a wide variety of uses and monitoring integrations
- Supports custom sensors built for in house applications
- Great option for companies looking for other monitoring solutions in the PRTG ecosystem
- Takes time to get used to the feature-rich interface
The free version of PRTG Network Monitor provides a well-stocked toolbox for monitoring a small network, download the free trial here. For more details, see The best free NetFlow analyzers and collectors for Windows.
Datadog Network Performance Monitoring watches over traffic across a network and also out on the internet to remote sites and cloud resources.
This package creates a network map and shows you traffic flows on each stretch in a live readout. Click on a device to get a detailed view of traffic volumes. This feature is called Flow Analytics. The system also generates graphs of traffic throughput at each device.
The visual data representations make traffic activity very easy to comprehend. This service can give more detailed if you access traffic tagging features.
The information given by the Network Performance Monitoring system gives you data on packet loss, latency, and jitter on each connection over time.
- Network traffic volume monitoring
- Internet connection analysis
- Performance alerts
Analytical features in the dashboard allow you to categorize traffic and get reports on volumes to, from, or between IP addresses. You can also see traffic per application or port.
Other features in this traffic monitoring system include DNS performance and cloud platform traffic activity for systems such as load balancers.
Any of the metrics that Datadog Network Performance Monitoring can have expectation thresholds placed on them. When crossed, these levels trip alerts. You can get these alerts forwarded to you by email or SMS, so you don’t need to watch the monitor all of the time – this feature automates network bandwidth monitoring.
- Traffic flows per link
- Drill-down views of switch activity
- Graphs for throughput per link, per application, or per port number
- Internet connection performance
- Doesn’t automatically include NetFlow, which is a plug-in feature
Datadog Network Performance is a subscription service with a rate per host per month. Datadog also offers a Network Device Monitoring system. Both of these tools can be experienced on a 14-day free trial.
ManageEngine produces a full network management suite and offers free versions of some of their tools. In our article on the best free NetFlow analyzers and collectors for Windows, we looked at the ManageEngine NetFlow Analyzer which provides real-time visibility into network bandwidth and traffic patterns, when you have devices that support NetFlow. The NetFlow Analyzer displays traffic by applications, conversations, protocols, etc; it can alert you to problems and has a range of report-generation options. Here we will focus on the Bandwidth Monitoring tool that is part of the free edition of ManageEngine OpManager.
The Bandwidth Monitoring tool leverages SNMP. It runs on Windows or Linux. The free edition supports monitoring three devices and their interfaces.
Figure 8: Devices and their interfaces, and alerts
Setting up the OpManager is a multi-step process but not overly complex. Once you provide the subnet and SNMP parameters, OpManager will scan your subnets and discover your devices. Then, from the inventory tab, you can check the status of devices’ interfaces. You can view graphs and tables of network usage, speed, and bandwidth, as well as device hardware metrics, either rolled up at the device level or drilling down to a particular interface.
Figure 9: Roll-up for an interface
Figure 10: Utilization graphs for an interface
At the interface level, you can generate reports showing bandwidth from the past 12 hours up to the past month. You can also set thresholds to receive automated alert email or SMS messages. By monitoring the gateway to your ISP, you can check your internet traffic usage and how much bandwidth you actually receive.
- Uses NetFlow
- Free version
- SNMP functions
The Bandwidth Monitoring tool combines with the other features of the free version of ManageEngine OpManager. This provides you with a well-rounded suite of capabilities for monitoring three devices or less on a small network.
- Features a host of additional network management tools to compliment bandwidth monitoring
- Offers a clean interface that combines visualizations with a trailing log of real-time reports
- Makes charting traffic patterns and high usage times easy with flexible visualization and alerting tools
- Inventory management feature could be reworked to be easier to filter and use
ntopng is an open-source web-based traffic analysis tool. The community version of ntopng is free; the professional (small business) and enterprise versions require buying a license. All versions do packet capture; the enterprise version also uses SNMP. To receive flow data ntopng depends on nProbe; a fully-functioning version of nProbe requires a paid license. Licenses are free to educational and nonprofit organizations.
Figure 12: Viewing flows
ntopng’s web-based user interface rolls up data into traffic (eg, top talkers), flows, hosts, devices, and interfaces.
- Packet capture
- Traffic flow statistics
- Community Edition is free to use
ntopng is a richly-featured open-source traffic and bandwidth monitoring tool. All editions are available for installation on Windows, Linux, Unix, macOS, and RaspbianOS.
- Open-source project with full transparency
- Free version available alongside the enterprise version
- Special licensing options for nonprofits and educational institutions
- Not the best option for larger multi-site networks
- Packet capture features are a bit limited
- User interface is easy to use, but could be improved upon
Nagios is a package of network monitoring services for networks, servers, and applications. The system is available in two version: Nagios Core and Nagios XI. Nagios Core is the original system and it is an open source project. You can use Nagios Core for free. The Nagios XI system is a paid tool that is built on top of the services underlying the Nagios Core version.
Both Nagios Core and Nagios XI include a network bandwidth analyzer.
- Live network traffic data
- Switch port activity monitor
Nagios uses the Simple Network Management Protocol (SNMP) to gather traffic data instead of the NetFlow system. SNMP defines device agent that make regular reports to an SNMP Manager. The reports include details about the device, such as its memory and CPU capacity. Each message shows the current utilization of both of those elements plus the traffic throughput on each port.
As the report also shows which device is connected to each port, the Nagios system is able to compile a live display of the traffic levels on each link and it also creates a network topology map showering those connections.
The Nagios system doesn’t just present network traffic information. You can also use the tool to monitor servers and applications. It is possible to extend the Nagios monitor with plug-ins that add on the capability to monitor specific products and applications.
- Network bandwidth capacity
- Traffic throughput display
- Network mapping
- Won’t run directly on Windows
You can download Nagios Core for free. All of the plug-ins that are available for Nagios XI also work with Nagios Core. Both editions of Nagios run on Linux. You can get them running on Windows over a hypervisor. Nagios XI is available for a 30-day free trial.
WhatsUp Gold is a network performance monitor that bwas created by Ipswitch but is now a product of Progress Software. The core package of WhatsUp Gold gathers data from network devics using the Simple Network Management Protocol (SNMP).
- NetFlow, sFlow, and J-Flow
- Status alerts
- Network performance monitor
- Traffic analysis add-on
The system can be expanded by add-on modules and one of those is the Network Traffic Monitor. You can’t get the traffic monitoring unit as a standalone package. The network performance monitoring services of the core package provides a foundation form the traffic analysis system. For example, the central WhatsUp Gold service creates a network device inventory and a live network topology map.
Traffic analysis facilities work with a wide range of flow-enabled devices, including NetFlow, sFlow, NetFlow-Lite, IPFIX, and J-Flow.
Dashboards are customizable. WhatsUp provides many canned reports, including reports for bandwidth and utilization; you can design customized reports, too.
The Network Traffic Monitor uses NetFlow, NetFlow-Lite, J-Flow, sFlow, and IPFIX to collect data from network switches. It helps you to implement traffic shaping methods by identifying application-specific traffic with NBAR and you can get CBQoS data through the system.
You can leave the WhatsUp Gold system to watch over traffic flows and let it alert you when a switch approaches its capacity. The alerting mechanism in the Network Traffic Monitor gives you time to get into the network management system and take evasive action to head off diaster. Alerts will be sent to you as notifications by email or SMS.
- Suitable for a multi-vendor network
- Combines network performance and traffic monitors
- Can support both virtual and physical hardware
- Balances user experience with monitoring features quite well
- Can’t be used individually without the core WhatsUp Gold
- Free version can only monitor up to five resources
WhatsUp Gold is marketed in bundles. The smallest bundle you can buy is called the Premium edition. You would pay for the Network Traffic Monitor as an add-on to that package. The full complement of WhatsUp Gold add-ons is included in the Total Plus edition. You could opt for the Network Admin Bundle, which includes the Network Traffic Monitor and a Network Configuration Manager with the core package. All WhatsUp Gold modules run on Windows Server. You can get a 30-day free trial of the core WhatsUp Gold system.
Choosing bandwidth monitoring tools
Several good free options are available to monitor the bandwidth of your network. Picking the appropriate one will depend on your installed network hardware, the size and sophistication of your network, and how you expect it to grow.
Network Bandwidth Monitoring FAQs
How to analyze network traffic remotely?
Many network monitoring tools are able to cover WANs, allowing one central network management team to monitor the networks at many sites. Cloud-based network monitoring tools all operate a remote monitoring system. In order to get around network security, these remote monitoring tools usually require an agent service to be installed on the remote network.
How can I view the bandwidth of my critical applications?
A typical network traffic monitor is able to identify traffic by application. This is possible because specific applications communicate on specific ports. The source and destination port numbers are always written in the packet headers that carry network traffic. If you don’t have a traffic monitor but use a packet sniffer, you can identify each application’s traffic by de-referencing the port numbers in the packets that you capture.
What is the best way to identify traffic flow on an existing network?
Networks are made up of a series of links. In order to get a useful overview of the entire network, it is necessary to examine traffic flows on each link. This can be done by measuring the traffic throughput on each router per destination. Creating your own map of the network and identifying traffic throughput on each link is complicated, so it is better to perform this task with a specialized traffic monitoring tool.