How to use Iperf to test the speed on Outdoor CPE in PtP Network

As you may know, the TP-Link Pharos CPE product has a built-in SpeedTest tool and it is based on Iperf too. However, its built-in SpeedTest tool can only be used in the PtP network between two TP-Link Pharos CPE products. What can I do when there is not just TP-Link Pharos CPE product in your PtP network?

This FAQ will tell you how to use Iperf to measure the speed of your TP-Link Pharos CPE in the PtP network. Before speed measurement, you need to prepare two computers.

Step 1: Install Iperf on computers

The test topology should be like this:

Download and install Iperf on the two computers (say PC A and PC B).

Here is the Iperf official website for downloading it:

https://Iperf.fr/Iperf-download.php

Please choose the corresponding software version for your computers when you download the Iperf software. For example, the system of PCs we used in this FAQ is Windows 64bit, so we download Iperf3-3.1.3-win64.

After downloading, we will get a zip file, extract it and we will have two files -- cygwin1.dll and Iperf3.exe like the following figure showing.

Copy these two files to the path C:\Windows\System32, and then the installation is completed.

Step 2: Configure Static IP for PC A/PC B/CPEs

Set up the topology as shown below:

In the diagram above, PC A is connected to the LAN port of the CPE(AP)’s adapter. PC B is connected to the LAN port of the CPE(AP)’s adapter.

Note: Please disable the firewall on both PCs before testing. The firewall may block test traffic.

Set the static IP address on both PC A and PC B.

For example, configure the PC A with IP address 192.168.0.100, Subnet mask 255.255.255.0. Configure the PC B with IP address 192.168.0.101, Subnet mask 255.255.255.0.

If you don’t know how to configure the IP info on a PC, please refer to this link.

Set the static IP address for both AP and Client CPE. The Default IP of the TP-Link CPE product is 192.168.0.254. Please set the AP and Client CPE with different IP addresses, like 192.168.0.254 for the AP and 192.168.0.253 for the Client CPE.

Step 3: Set Iperf Server and Client to measure the speed

When using Iperf to test the speed, we need to set one PC as a server and another PC as a client, in this FAQ we set PC A as a server and PC B as a client.

On PC A, press the Windows key & R key on your keyboard, then put “cmd” in the Open bar and click OK to run cmd.exe.

In the popping out cmd window, input the command "iperf3 -s" and press enter, you will get a message of Server listening…, which means the PC is set as Iperf server now.

The same operation on PC B to run cmd.exe.

In the popping out cmd window, input the command "Iperf3 -c 192.168.0.100", the “-c” means to set PC B as Iperf client, and the IP address behind “-c” is the IP address of the server. After inputting this command, click Enter to start measuring the speed.

As showing in the above figure, we can see the speed result is 95 Mbps, this is the throughput value for this PtP wireless connection.