Python ICMP Ping Utility

Overview

This project is a custom-built implementation of the standard Ping network utility. Developed for Deakin unit SIT323, it demonstrates low-level network programming by constructing and parsing Internet Control Message Protocol (ICMP) packets manually.

Unlike basic implementations that call system-level ping commands, this application utilizes Python raw sockets to interface directly with the network layer (OSI Layer 3).

Key Features

• Manual Packet Construction: Uses struct.pack to build ICMP Echo Request headers (Type 8) with a 16-bit identifier based on the current Process ID.
• Checksum Implementation: Includes a custom calc_checksum function that performs 16-bit word summation and one's complement folding as per RFC 792.
• Header Parsing: Extracts TTL from the IP header and unpacks ICMP fields (Type, Code, ID, Sequence) using struct.unpack.
• Validation Logic: Rigorously validates incoming replies by comparing Request IDs and Sequence numbers to ensure response integrity.
• RTT Calculation: Measures round-trip time in milliseconds with 3-decimal precision, implementing a 1-second interval between successive pings.

Technical Requirements

• Python 3.x
• Administrative/Root Privileges: Because this application uses Raw Sockets (socket.SOCK_RAW), it must be executed with elevated privileges:
  • Windows: Run PowerShell/CMD as Administrator.
  • macOS/Linux: Prefix the execution command with sudo.

Installation & Usage

1. Clone the repository:

   git clone [https://github.com/rory-cd/ping.git](https://github.com/rory-cd/ping.git)

2. Navigate to the directory:

   cd python-ping-utility

3. Run the application:

    # Linux/macOS
    sudo python3 ping.py
   
    # Windows (Run as Admin)
    python ping.py