Building a Port Scanner with Python

# Introduction

In this project, we will develop a server port scanner using Python to detect open ports on a target server. This tool is crucial for both system administrators, who use it to verify security policies, and potential attackers, who use it to identify operational network services on a host. Our journey will cover the essential aspects of port scanning, including its methodology and implications. We'll delve into creating a simple yet effective port scanner leveraging Python's capabilities, focusing on a multi-threaded approach to enhance efficiency and performance.

Port scanning is the process of sending requests to a range of server ports to determine which ones are open. This step is crucial for both maintaining security and for attackers to find vulnerable services. We'll start by exploring the basics of port scanning and its implications.

Key Concepts:

- Port scanners help in detecting open ports on a server or host.
- They are used for security assessments and by attackers to identify vulnerable services.
- The simplest form of port scanning involves attempting TCP connections to a range of ports.

## 👀 Preview

Here's a sneak peek at the port scanner tool we'll be building:

python port_scanner.py 127.0.0.1 5000-9000

Output:

Opened Port: 8081
Scanning completed.

## 🎯 Tasks

In this project, you will learn:

- How to utilize Python's socket programming capabilities to interact with network ports.
- How to implement a multi-threaded approach in Python to enhance the efficiency of network scanning tasks.
- How to develop a command-line tool in Python that takes user inputs for flexible port scanning.

## 🏆 Achievements

After completing this project, you will be able to:

- Use Python's socket library to create network connections, test port availability, and handle network exceptions.
- Understand and apply multi-threading in Python to perform concurrent tasks, significantly improving the performance of network-intensive operations.
- Build a practical command-line port scanner tool, enhancing your Python scripting skills and understanding of command-line argument parsing.