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> Use this file to discover available pages before exploring further.
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# 🧪 iPerf3 Network Speed Testing Guide

**iPerf** is an open-source network performance measurement tool developed by the Internet Performance Working Group. It allows users to test network throughput by creating **TCP** or **UDP** streams and sending traffic from one host (client) to another (server). The results show the **maximum achievable bandwidth**, helping diagnose network issues or validate performance.


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## 🧩 TCP vs. UDP – What’s the Difference?

| Protocol | Connection Type | Reliable? | Use Case |
| ---- |
| **TCP** | Connection-based | ✅ Yes | File transfers, web browsing |
| **UDP** | Connectionless | ❌ No | Streaming, VoIP, gaming |

* **TCP** uses a *three-way handshake* to ensure reliable delivery.
* **UDP** sends data without establishing a connection, making it faster but less reliable.

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## 🖥️ Installing iPerf3

### Linux (Debian-based systems)

1. Log in to your Debian-based system.
2. Run:

```
   sudo apt-get install iperf3
```
3. Press **Y** when prompted to confirm installation.

![](https://ggcircuit.atlassian.net/wiki/download/attachments/15863551/image-20240526-205835.png?version=2&modificationDate=1752497969781&cacheVersion=1&api=v2)

### Windows

1. Download iPerf3: [https://files.budman.pw/](https://files.budman.pw/)
2. Extract the zip file to a known location, e.g., Desktop.

![](https://ggcircuit.atlassian.net/wiki/download/attachments/15863551/image-20240526-212744.png?version=2&modificationDate=1752497986633&cacheVersion=1&api=v2)

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## ▶️ Running iPerf3

### Step 1: Start iPerf3 Server on Debian

On the Debian machine:

```
iperf3 -s
```

This starts the server in **listening mode**, waiting for a client connection.

![](https://ggcircuit.atlassian.net/wiki/download/attachments/15863551/image-20240526-211320.png?version=2&modificationDate=1752498013116&cacheVersion=1&api=v2)

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### Step 2: Run iPerf3 Client on Windows

1. Open **Command Prompt**.
2. Navigate to the extracted iPerf3 directory:

```
   cd C:\Users\YourUsername\Desktop\iperf3
```

![](https://ggcircuit.atlassian.net/wiki/download/attachments/15863551/image-20240526-211746.png?version=2&modificationDate=1752498032511&cacheVersion=1&api=v2)

3. Run the client test:

```
   iperf3.exe -c
```

![](https://ggcircuit.atlassian.net/wiki/download/attachments/15863551/image-20240526-212014.png?version=2&modificationDate=1752498057322&cacheVersion=1&api=v2)

To run a **reverse test** (measuring download on client):

```
iperf3.exe -c -R
```

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## 📊 Interpreting the Results

### Sample Output

If you're testing from a remote client, the output will show:

* **Sender (Client)**: Measures **upload** from client to server.
* **Receiver (Server)**: Measures **download** from client to server.

You can swap directions using the `-R` flag on the client to test the opposite path.

![](https://storage.crisp.chat/users/helpdesk/website/-/a/f/d/6/afd6941e8bc7d800/image-20240526-212135_qypr50.png)

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## 🎥 Video Tutorial

![](https://ggcircuit.atlassian.net/wiki/download/attachments/15863551/iperf.webm?version=2&modificationDate=1752498257353&cacheVersion=1&api=v2)

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