How to Test Client Speed and Traffic Shaping Using Jperf

Overview

Jperf is a free, Java-based graphical user interface (GUI) tool that performs the same functions as Iperf. It is designed for those who prefer graphical output and point-and-click functionality. Jperf is useful for measuring throughput and jitter between two devices on a local area network (LAN) or wide area network (WAN). 

Online speed tests such as speedtest.net or speakeasy.net are not highly accurate. They introduce considerable delays and uncertainty to the measurement.  

Factors such as test server location, concurrent Internet activity, and proxy server participation can affect online test results. These factors introduce additional network activity to the measurement. Using Jperf provides an unbiased measurement of LAN and WLAN throughput without introducing uncontrollable variables.  

This article describes how to install and use Jperf to test data throughput. One hosts connects via wireless access; the other connects via wired access.

Refer to the diagram below. 

Prerequisites 

Before starting, confirm the following requirements are met: 

• Two networked computers that can access each other through your local LAN or WLAN 

• Java installed and supported on both computers 

Step-by-step instructions 

This section describes how to test wireless and wired throughput between two hosts connected through a Cisco Meraki MR access point and switch.  

1. Download Jperf (for Windows). 
2. Extract the Jperf file to your desktop. 
3. Open the Jperf  folder and run the jperf batch file (You need Java installed in your workstation).  

4. The following Jperf GUI opens. Repeat this procedure on both workstations.

 

 

On host B (server):

5. Under Choose iPerf Mode, select Server. 

6. The "Listen port" is set to 5001 by default. Change the port as needed. 

7. Select Run Iperf.

8. When prompted, allow inbound access to the Iperf server ports in Windows Firewall. 

On host A (client):

9. Under Choose iPerf Mode, select Client. 

10. Enter the server's IP address and port. The default port is 5001.

11. Select Run Iperf. 

12. A Bandwidth and Jitter graph is generated. A command output with test results is also available. 

Verification 

After completing the steps above, confirm the following to verify the task completed successfully: 

• A Bandwidth and Jitter graph is displayed in the Jperf GUI 

• A command output is available alongside the graph, showing the test results