Network Backbones (Devices)

Two or more computer connected to each other makes a network. Computers are not individually connected to one another. Some other devices that connect and Internet, we call that devices network backbones. These make the LAN. Backbones help the network to share the data. Data that are share in a network are in different forms. Backbone devices work on highly complex data that is share in the network. Backbone devices are work on different layers of Network Model.

We will discuss some important devices that are commonly used in home, office and mills.

• Hub
• Switch
• Router
• Bridge
• Gateway

Hub:

Hubs in a network just connect the computers and share data. Hub is less used as compare to the other devices. This is use in low level only in LANS. For example: 

We want to send the message to a computer in a network. Hubs send this message to all the computers in a network. Reason: For the confirmations that message have reach their destination.

                           

The biggest disadvantage of a hub is that the heavy load is placed on the network.

There are two types of hubs.

• Passive Hub
• Active Hub

• Passive Hub:

Passive hub is work as a connector in a network, it connect the wires that are coming from            different points and branches. In star-topology Ethernet LANS, passive hub is a central point where    all the signals are collide that comes from different points and branches. Passive Hub in network      layer model works below the physical layer.

• Active Hub:

An active hub is actually a multi-port repeater. It is normally used to create connection between stations in physical star topology. 

Switch:

Switches are more intelligent as compare to the hubs. A switched network consists of series of interlinked nods. Two or more devices are connected to the switch. Switches are capable of creating temporary connection. Switches connect the devices one of the

points is connect to the end system. Switches send messages direct to the destination unlike hubs. 

 Switches are working on two layers of network layer model data link layer and network layer.

Router:

Router is also a backbone device. That connects the LANS and WANS in a network. Routers send

data in the form of packets. Routers sends the messages through the logical Addresses of destination point. Router works on three layers of network in layer model.

Bridge:

As name denoted bridge connect the two edges. Act as a supporter. Bridge work on two layers of network layer modal physical layer and data link layer. Bridge sends message or data in the form of frame. Physical layer in bridge regenerate the signals and the data link layer check the MAC addresses of the source and destination.

Gateway:

Gateway normally is a computer, that take the message , read it and interpret it. This means it is act as

 a connecting devices between internetwork that use different model. Gateway normally works on five layer or seven layers of the network model. If transfer message or data in the form of frames.

These are the most commonly used backbone devices that I have discuss above.