Collision vs broadcast domains: Which statement about what a switch and a router create is true in a default, non-VLAN Ethernet LAN?
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AA switch creates a single collision domain and a single broadcast domain. A router creates a single collision domain.
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BA switch creates separate collision domains but one broadcast domain. A router provides a separate broadcast domain.
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CA switch creates a single collision domain and separate broadcast domains. A router provides a separate broadcast domain as well.
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DA switch creates separate collision domains and separate broadcast domains. A router provides separate collision domains.
Answer
Correct Answer: A switch creates separate collision domains but one broadcast domain. A router provides a separate broadcast domain.
Explanation
Introduction / Context:Designing Ethernet LANs requires distinguishing how switches and routers segment traffic. Switches break up collisions; routers break up broadcasts. This determines scalability and performance.
Given Data / Assumptions:
- No VLANs are configured; one VLAN, one broadcast domain across the switch.
- Switch ports operate as individual collision domains.
- Routers separate broadcast domains at Layer 3.
Concept / Approach:Each switch port is its own collision domain; hence, a switch creates many collision domains but still one broadcast domain per VLAN. A router does not forward broadcasts between interfaces, thereby creating distinct broadcast domains on each interface/subnet.
Step-by-Step Solution:
Switch: multiple collision domains (per port) + one broadcast domain (per VLAN).Router: separates broadcast domains by subnets (no L2 broadcast forwarding).Match to answer set → option describing separate collisions for switch and separate broadcast domains via router.Verification / Alternative check:Simple lab: ARP broadcast will traverse all switch ports in a VLAN, but not pass through the router to another subnet.
Why Other Options Are Wrong:Options claiming a switch creates multiple broadcast domains are wrong without VLANs. Options claiming a router creates only collision domains misunderstand L3 behavior.
Common Pitfalls:Equating switch segmentation with broadcast segmentation; only VLANs or routers segment broadcasts.
Final Answer:A switch creates separate collision domains but one broadcast domain. A router provides a separate broadcast domain.