Network+ Training Guide

The Layers at Which Devices Operate

• Identify the OSI layers at which various network components operate including:

  • Hubs

  • Switches

  • Bridges

  • Routers

  • Network interface cards (NICs)

Now that we have examined the OSI network layer in some detail, we can look at how it relates to the network connectivity devices discussed in Chapter 3: hubs, switches, bridges, routers, and network interface cards (NICs). These devices are said to operate at certain layers of the OSI model based on their functions and roles in the network. Because these devices are covered in Chapter 3, this chapter does not describe them in detail. Instead, this chapter contains a brief description of each device, to jog your memory.

Hubs

Hubs act as the connectivity points of the network ...