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Clarify how an automatic repeat request (ARQ) system ensures that data is received accurately, including the roles of positive and negative acknowledgments and the concept of timeouts.

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Cambridge IGCSE Computer ScienceData transmission

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Clarify how an automatic repeat request (ARQ) system ensures that data is received accurately, including the roles of positive and negative acknowledgments and the concept of timeouts

This point belongs to Methods of error detection, especially Methods of error detection outcomes.
You need to be able to clarify how an automatic repeat request (ARQ) system ensures that data is received accurately, including the roles of positive and negative acknowledgments and the concept of timeouts.
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Description

Automatic Repeat Request (ARQ) System

An ARQ system uses positive and negative acknowledgments to ensure data integrity during transmission. If a packet is received correctly, a positive acknowledgment (ACK) is sent. If there is an error, a negative acknowledgment (NACK) is sent, prompting retransmission. Timeouts are also implemented to manage the waiting period for acknowledgments.

a
Explain the role of positive and negative acknowledgments in an ARQ system.
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Recognize the importance of verifying data after it has been transmitted and understand the potential causes of errors during this process, such as data loss, gain, or alteration due to interference.
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Explain the steps involved in various methods used to detect errors in transmitted data, specifically focusing on parity checks (both odd and even), checksums, and echo checks, including details on parity bytes and blocks.
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