The document discusses flow and error control protocols, including stop and wait, stop and wait ARQ, go-back-n ARQ, and selective repeat ARQ, focusing on their mechanisms, advantages, and disadvantages. These protocols are essential for reliable communication in networks, each suited to different conditions and requirements. Challenges include increased complexity and resource utilization, with future trends pointing towards adaptive mechanisms and AI integration.

1. Flow and Error control Protocols
Contributions -
❏ Shubham Singh (22BCY10185)
❏ Rohan Mishra (22BCY10173)
❏ Anipra Pandya (22BCY10172)
❏ Priyanshu Gautam (22BCY10141)
❏ Adhil Ali (22BCY10163)
Stop and Wait, Stop and Wait ARQ
Go back-N ARQ, Selective repeat ARQ.

2. Introduction
● What are Flow and Error Control Protocols?
○ Flow Control: Manages the pace of data
transmission to avoid receiver overflow.
○ Error Control: Ensures data integrity through error
detection and correction techniques.
○ Key Protocols: Stop and Wait, Stop and Wait ARQ,
Go-back-N ARQ, and Selective Repeat ARQ.
● Why Are They Important?
○ Provide reliable communication in networks prone to
errors or delays.
○ Enhance the efficiency and robustness of data
transfer.
Shubham Singh

3. Stop and Wait Protocol
Overview:
● Sender transmits one frame, then waits for an
acknowledgment before sending the next.
● Simple but has significant idle time during waiting.
Advantages:
● Easy to implement.
● Low resource requirement.
Disadvantages:
● Inefficient for high-latency networks.
● Poor utilization of bandwidth.
Shubham Singh

4. Stop and Wait ARQ
● Overview:
○ Extends Stop and Wait by adding error-checking
and retransmission.
○ Timeout mechanism ensures lost or corrupted
frames are retransmitted.
● Advantages:
○ Guarantees reliable delivery even in error-prone
channels.
○ Simple error-handling mechanism.
● Disadvantages:
○ Still suffers from high latency and low throughput.
○ Inefficient for large data transmissions.
Rohan Mishra

5. Go-back-N ARQ
● Overview:
○ Allows sending of multiple frames within a window
size without waiting for individual ACKs.
○ Retransmits all frames from the point of error
onward.
● Advantages:
○ Improves bandwidth utilization compared to Stop and
Wait.
○ Reduces idle time for the sender.
● Disadvantages:
○ Inefficient for high error rates due to redundant
retransmissions.
● Use Cases: Ideal for moderate-speed, reliable networks.
Rohan Mishra

6. Go-back-N ARQ Diagram
Rohan Mishra

7. Selective Repeat ARQ
Overview:
● Only the erroneous frames are retransmitted, not the entire window.
● Receiver stores out-of-order frames until the missing one is
received.
Advantages:
● Higher efficiency and better bandwidth utilization.
● Suitable for high-speed networks.
Disadvantages:
● Increased complexity in buffering and sequence management.
● Requires additional memory and processing power.
Use Cases: Real-time applications requiring minimal retransmissions.
Priyanshu Gautam

8. Selective ARQ
Diagram Priyanshu Gautam

9. Comparison of Protocols
Priyanshu Gautam

10. Real-World Applications
Stop and Wait Protocol
● Use Cases:
○ Simple IoT communication systems.
○ Basic remote sensors with low data throughput
requirements.
● Example: Temperature sensors transmitting periodic data.
Stop and Wait ARQ
● Use Cases:
○ Wireless communication with moderate error rates.
○ Basic email transmission over error-prone networks.
● Example: Messaging apps with small payload sizes. Anipra Pandya
22BCY10172

11. Real-World Applications (Cont.)
Go-back-N ARQ
● Use Cases:
○ High-latency systems requiring bulk data transfer.
○ File transfers in moderately reliable networks.
● Example: FTP (File Transfer Protocol) operations.
Selective Repeat ARQ
● Use Cases:
○ High-speed real-time communication systems.
○ Networks where bandwidth conservation is
critical.
● Example: Live video streaming platforms like YouTube. Anipra Pandya
22BCY10172

12. Challenges and Limitations
General Challenges:
● Increased protocol complexity for enhanced
features.
● Trade-off between efficiency and resource usage.
Specific Limitations:
● Stop and Wait: High idle time.
● ARQs: High memory and computational
requirements.
● Selective Repeat: Complexity in managing
sequence numbers.
Adhil Ali

13. Conclusion
● Summary:
○ Flow and error control protocols ensure efficient and
reliable communication.
○ Each protocol has specific strengths and weaknesses
tailored to network conditions.
● Key Takeaway: The choice of protocol depends on the
trade-off between efficiency, complexity, and reliability.
● Future Trends:
○ Adaptive error
control mechanisms.
○ Integration with AI for
predictive
retransmission.
Adhil Ali