Hub is that the central point of networking device that connects multiple hosting devices to one network. It allows data to urge transferred between themselves by functioning as a multi-port repeater. For this purpose, it uses either fibre optic cable or a twisted pair cable.
It is a networking device that allows connecting multiple Ethernet devices (i.e. hosts) using twisted pair or fibre optic cable. It operates at the Physical Layer i.e. layer-1 of OSI stack. Generally, the hub works on (Physical layer) a bit like switches it also connects computers together.
It functions as a multi-port repeater which broadcasts data to all or any the ports where devices are connected. Following are features of the network hub device –
- Operates in half-duplex mode.
- Available in 4 to 24 port sizes.
- Hosts are liable for collision detection.
- There are three types of viz. active hub, passive hub and intelligent hub.
Advantages of Hub :
-
Connectivity –
The primary function of the hub is to permit clients to attach to a network in order that they will share and have conversations. For this purpose, hubs use network protocol analyzer.
-
Performance –
Hub is understood for having very less number of performance impacts on the network. This is often because it operates using a broadcast model which rarely affects the network.
-
Cost –
Comparing to switches, hubs are really inexpensive. Basically thanks to its sort of simplicity. Therefore, they will assist you to save lots of money. And also due to their products they are widely available within the market.
-
Device Support –
Hubs can connect different types of media all at once with a central hub. Albeit the media want to operate at different speeds they will be wont to support them.
-
Area Coverage –
Area coverage of a network is restricted to a certain distance. Hub extends the space of the network such communication is formed easy.
Disadvantages of Hub :
-
Collision Domain –
The function of the collision domain and again transfer of packet does not affect actually it increases more chances of collision in between domains.
-
Full-Duplex Mode –
Hubs cannot communicate fully duplex mode, it can only operate in half-duplex mode. Half-duplex mode, in essence, means data are often transmitted just one occasion at a given time. Therefore, the hub must constantly switch its modes.
-
Specification –
Hubs cannot support networks that are large like a token ring. This is often because hubs must share data among all the devices within the network.
-
Network Traffic –
As the attachment was received in the packet so it cannot reduce traffic. Hence, hubs make a high level of network traffic.
-
Bandwidth Wastage –
Hubs cannot provide dedicated bandwidth for every device, it is to share them. When sending large pieces of information all the bandwidths are going to be occupied by the two computers leaving other computers with slow network.