Interactive visualization of the Selective Repeat Automatic Repeat Request protocol
Timeline Diagram
📋 Transmission Log
Learn About Selective Repeat ARQ
Selective Repeat ARQ (Automatic Repeat Request) is a data link layer protocol that allows the sender to
have multiple unacknowledged frames in flight. Unlike Go-Back-N, it only retransmits frames that are
lost or damaged, making it more efficient for networks with high error rates or long propagation delays.
Key Concepts
Sliding Window: A mechanism that allows multiple frames to be in transit.
Selective Retransmission: Only corrupted or lost frames are retransmitted.
Receiver Buffer: The receiver maintains a buffer to store out-of-order frames.
👥 Meet the Team
Project Developers
Ujjwal Shukla
Reg No: 24BCE5349
Email: ujjwal.shukla2509@gmail.com
SCOPE
Vasu Jindal
Reg No: 24BCE5445
Email: vasu.jindal2024@vitstudent.ac.in
SCOPE
Praharsh Agarwal
Reg No: 24BCE1886
Email: praharsh.agarwal2024@vitstudent.ac.in
SCOPE
Faculty Guide
Dr. A Swaminathan
Professor at VIT Chennai
Project Information
Course: Computer Networks
Institution: VIT Chennai
Year: 2025
Help & User Guide
1Configure Parameters
Number of Frames: Total frames to transmit (e.g., 8)
Window Size: Sliding window size (e.g., 4).
Delay/Loss Modes: For both Frames and ACKs, choose a mode:
None: Perfect transmission.
Random: A 25% chance of loss/delay for any packet.
User Defined: Specify one exact frame/ACK number to lose/delay (e.g., 3).
Every Kth: Lose/delay every Nth packet (e.g., 2, 4, 6...).
2Run the Simulation
Click "Start Simulation". The simulation will run based on your selected mode.
3Interpret the Diagram & Log
Green Line: Successful Frame transmission.
Blue Line: Successful ACK.
Red Line (Solid): Lost Frame.
Gray Line (Dashed): Lost ACK.
Orange Line (Dashed): Retransmitted Frame.
Red Text: Timeout event at the sender.
The Transmission Log below the diagram shows a step-by-step text record of all
events.
4Reset
Reset: Clears the diagram and log for a new simulation.