Which option best defines a communication network in the context of data communications among attached stations?
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Aone or more conductors serving as a common connection for a related group of devices
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Ba continuous frequency capable of being modulated or impressed with a second signal
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Cthe condition when two or more stations attempt to use the same channel simultaneously
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Da collection of interconnected functional units that provides a data communications service among stations attached to the network
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ENone of the above
Answer
Correct Answer: a collection of interconnected functional units that provides a data communications service among stations attached to the network
Explanation
Introduction / Context: A communication network is more than a wire or a radio channel; it is an organized system that interconnects devices and provides end-to-end data transfer services according to protocols and architectures.
Given Data / Assumptions:
- We focus on the system as a whole, not a single medium or fault state.
- Stations are attached nodes (hosts, routers, switches).
- Service includes addressing, routing/switching, and reliable delivery functions.
Concept / Approach: A network comprises functional units (links, switches, routers, protocols, management) that cooperate to deliver communication between stations. This holistic definition distinguishes “network” from “bus,” “carrier,” or “collision.”
Step-by-Step Solution: Identify the definition that references interconnected units plus provided service.Exclude options that describe only media (conductors, carriers) or error states (collisions).Select the comprehensive system-level description.
Verification / Alternative check: Standard textbooks define networks as interconnected nodes/links implementing protocols that provide communication services.
Why Other Options Are Wrong: Conductors: Describes a physical bus/backplane, not a network.
Continuous frequency carrier: Describes a channel characteristic. Collision condition: A transient MAC-layer event, not a network. None of the above: Incorrect because one option is correct.Common Pitfalls: Confusing a medium (wire/radio) with the layered services that make up a network.
Final Answer: a collection of interconnected functional units that provides a data communications service among stations attached to the network