ricardoyang00 / feup-rcom-datalink-protocol

Data Link Protocol of RS-232 serial cable (includes macOS instructions)

Data Link Protocol

This project was developed as part of the Redes e Computadores (RCOM) course to develop a data link protocol to enable file transfer between two computers connected via an RS-232 serial cable, by implementing both transmitter and receiver functionalities.

Project Structure

• bin/: Compiled binaries.
• src/: Source code for the implementation of the link-layer and application layer protocols.
• include/: Header files for the link-layer and application layer protocols.
• cable/: Virtual cable program to help test the serial port. This file must not be changed.
• main.c: Main file.
• Makefile: Makefile to build the project and run the application.
• penguin.gif: Example file to be sent through the serial port.

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Quick Start

Important

For macOS users, please read this guide.

1. Compile the Application and Virtual Cable Program

   • Use the provided Makefile to compile the project:

     make

2. Run the Virtual Cable Program

   • You can run the virtual cable program manually or using the Makefile target:

     sudo ./bin/cable_app

     sudo make run_cable

3. Test the Protocol Without Cable Disconnections and Noise

   3.1 Run the Receiver

   • Run the receiver manually or using the Makefile target:

     ./bin/main /dev/ttyS11 9600 rx penguin-received.gif

     make run_rx

   3.2 Run the Transmitter

   • Run the transmitter manually or using the Makefile target:

     ./bin/main /dev/ttyS10 9600 tx penguin.gif

     make run_tx

   3.3 Verify the Received File

   • Check if the received file matches the sent file using the diff command or the Makefile target:

     diff -s penguin.gif penguin-received.gif

     make check_files

4. Test the Protocol With Cable Disconnections and Noise

   4.1 Run the Receiver and Transmitter Again

   • Follow the same steps as in section 3 to run the receiver and transmitter.

   4.2 Simulate Cable Disconnections and Noise

   • Quickly switch to the cable program console and use the following commands:
     • off: Simulate unplugging the cable.
     • ber <value 0-1>: Add noise with a specified bit error rate.
     • ber 0: Return to normal operation.

   4.3 Verify the Received File

   • Check if the received file matches the sent file, even with cable disconnections or noise, using the diff command or the Makefile target:

     diff -s penguin.gif penguin-received.gif

     make check_files

Statistics and Report

For detailed report, click here.