|  | 5.4 | Layer 1 Components and Devices
| 5.4.7 | Repeaters

Repeaters regenerate, and retime signals, which then enables cables to extend farther to reach longer distances. They only deal with packets at the bit level, therefore they are Layer 1 devices. Repeaters are internetworking devices that exist at the physical layer (Layer 1) of the OSI model. They can increase the number of nodes that can be connected to a network, and thus, the distance over which the network can extend. Repeaters re-shape, regenerate, and retime signals before sending them on along the network.

The disadvantage of using repeaters is that they cannot filter network traffic. Data (bits) that arrive at one port of a repeater are sent out on all other ports. The data gets passed along to all other LAN segments of a network regardless of whether or not it needs to go there.