Below is a list of interconnection devices for computer networks. This includes a simple definition and how a brief explanation on how they differ.

 

Hubs

Device classification - dumb

The hub amplifies signals and transmits the signals to all the computers attached to it.

 

Switch

Device classification - intelligent

The switch Looks at the messages and the address and send it to the right computer.

This device also cuts down on network traffic and it cost more.

 

Repeater

Device classification - dumb

The repeater amplifies signals. It is used to extend the length of a network cable, but it has a physical limit of 1000 meters.

 

Bridge 

Device classification - intelligent

The bridge is used to connect two separate LANs.  It is also used to filter messages.

 

Router

Device classification - intelligent

The router is similar to a bridge in that, looks at the packets and stores address in memory and also routes to different LANS.

 

Gateway

Device classification - intelligent

As the name implies, the gateway translates one network to the other, E.g. from windows 2000 to mackintosh network.

 

Concentrator

Device classification - dumb

The concentrator is similar to the hub; it serves as a central connection point for several terminal devices.

 

Working with the OSI model :

  • The hub operates with the physical layer of the OSI
  • The repeaters operate with the physical layer
  • The switches operates with the data link layer of the OSI
  • The bridges also operates with the data link layer
  • The routers operates with the network layer of the OSI
  • The gateways also operate with the network layer of the OSI

 

Basically, switches may operate with the data link layer of the OSI. However, it may also operate with other layers such as the physical layer, the transport or the network layer.

Unlike routers, switches do not have the capability to collect data about traffic patterns.