What is a collision domain?

• A. A Set Of Devices That Receive All Broadcast Frames.
• B. If Two Nodes Send Out Packets At The Same Time, A Collision Occurs And The Packets Are Lost.
• C. A Device That Prevents Collisions.
• D. A Type Of Switch.

Answer: (B)

A collision domain is the network area where multiple devices share the same communication medium and can cause collisions if they transmit simultaneously. On Ethernet networks that use hubs or repeaters, all devices on that segment contend for the same bandwidth, so two devices transmitting at the same time can collide, garbling both frames. The devices then detect the collision and use a backoff scheme to retry. This is why the behavior described—two nodes sending at once leading to a collision—is the defining feature of a collision domain. Switches break up collision domains by giving each port its own separate segment, so collisions don’t propagate across ports.