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Collision Domain

Hubs and Switches are used to interconnect LANs, but there are important differences between these devices. Firstly, they operate on different layers.

Since a Hub works in the physical layer, it does not examine addresses, but instead sends incoming frames to all interfaces. Thus, all nodes connected by a hub belong to the same collision domain. That is, whenever two or more stations transmit at the same time, a collision will occur.

A Switch operates on the data link layer. It stores incoming frames and forwards it based on the destination MAC address. In contrast to a hub, each LAN segment connected to an interface of the switch is an isolated collision domain.

In this small game you have to decide if a collision will occur. One after the other you'll see different scenarios with always 2 parallel communications (a red sender (S) sends to the red receivers (R) and a green sender to the green receivers). Decide for each scenario if a collision occurs and press the appropriate button (the flash represents a collision and the crossed out flash stands for "no collision"). Just press start!