1 of 12

Network Devices

Repeaters, hubs, bridges, switches, routers, NIC’s

2 of 12

Devices and the layers at which they operate

Layer

Name of Layer

Device

3

Network

Routers, layer 3 switches

2

Data Link

Switches, bridges, NIC’s

1

Physical

Hubs, Repeater

3 of 12

NIC’s �(Network Interface Cards)

  • This NIC has interfaces for twisted pair, thicknet, and thinnet connectors.

4 of 12

Repeaters

  • Signal attenuation or signal loss – signal degrades over distance

​

  • Repeaters can amplify week signal,

and resend signal to next segments

to increase range.

  • Built-in to hubs or switches

5 of 12

Hubs

  • OSI layer 1 hardware
  • Hubs regenerate and retime network signals
  • Hubs propagate signals through the network
  • They cannot filter network traffic
  • They cannot determine best path
  • They are used as network concentration points
  • They are really multi-port repeaters
  • Uplink port – crossover mode or straight through mode

6 of 12

Bridges

  • A layer 2 device
  • Connect two or more LAN segments, each of which is a separate collision domain.
  • The purpose is to filter traffic on a LAN, to keep local traffic local, yet allow connectivity to other segments of the network.
  • Filter traffic by looking at the MAC address
  • Frame filtering

7 of 12

bridges

8 of 12

Switches

  • Each port is a simulated segment to itself
  • Filtering logic circuit.

​

9 of 12

Switches

10 of 12

Router

  • Define Route between source to destination.
  • Connect different LAN, WAN

11 of 12

Gateway

  • Provide service to connected & authorized hosts. / nodes.

12 of 12

End �?