A network hub is a simple device used to connect multiple devices in a local area network (LAN) and operates at the physical layer in the OSI (Open Systems Interconnection) model. The primary function of a network hub is to receive incoming data packets from one of its ports and then broadcast the data to all other connected ports, regardless of the destination.
What is Network Hub?
A hub is a common connection point for connecting devices in a network, called as network hub. It works as a central connection for all the devices that are connected via hub. This hub has numerous ports and if a packet reaches at one port, this hub can see all the segments of the network as the packet is copied to other ports. The network hub does not have routing tables unlike network switch or router that is sued to send information and broadcast all the data network across all the connections.
Further to know more, hub does not have IP address. In the earlier times, network hubs were very popular as they were not expensive when compared to switch or router. But, in the current days, switches are cheaper than the hub and they provide a better solution for any network.
Types of Hubs
There are three types of hubs –
Passive Hub
It is a connecting point for wires which helps to make the physical network. It has the ability to locate the bug and faulty hardware. Passive hub accepts the packet over a port and distributes it to all the ports available.
These hubs would add connectors which can be applied as standard in the network and this connector is connected to all (Local Area Network) LAN devices. Also, the advanced passive hubs contain AUI ports that are connected as the transceiver as per the design of the network. However, passive hubs do not amplify the electric signal.
Active Hub
This hub has additional features when compared to passive hub. It can monitor the data that is sent to the devices connected. With the help of store technology, active hubs play a vital role between the connected devices.
Additionally, it checks the data that is to be sent and finalizes which packet to be first sent. Moreover, the active hub are capable to fix the damaged packets while sending, hold the direction of the remaining packets, and distribute them.
Intelligent Hub
These intelligent hubs are little advanced when compared to passive and active hubs. They have some kind of management software which helps to analyze the problem in the network and resolve them.
It is advantageous to expand business in networking. The management can assign the users which help to work more quickly and share a common pool efficiently by using intelligent hubs. Also, it offers better performance for local area networks. If there is any issue is detected, with the support of any physical device it can detect the problem easily.
Features of Hub
- It acts with shared bandwidth and broadcasting.
- It has only one clash domain and broadcast domain.
- Hub works on the physical layer of the OSI model and it also supports for half duplex transmission mode.
- Hub cannot create a virtual LAN and does not support spanning tree protocol.
- More importantly, packet collisions happen inside the hub.
- Hub has the feature of flexibility i.e, it includes a high transmission rate to different devices.
Applications of Hub
Below are some of the main applications of hubs mentioned –
- To create small home networks.
- Used for network monitoring.
- They are used in organizations in order to provide connectivity.
- Hub can create a device that is available all throughout the network.
Working of Hub
A network hub typically has multiple ports where network cables (usually Ethernet cables) from different devices are connected. Devices like computers, printers, servers, and other network-enabled devices. When a device sends data (such as a file or a request) to the network hub, the hub receives the data and broadcasts it to all other devices connected to its ports. This broadcasting mechanism means that every device connected to the hub receives the data, regardless of whether it is the intended recipient or not.
One significant limitation of hubs is that they create a single collision domain. In networking, a collision occurs when two or more devices try to send data over the network simultaneously, leading to data corruption. Since a hub broadcasts data to all devices, collisions can occur frequently in a hub-based network, especially as the number of connected devices increases.
Unlike switches or routers, hubs lack intelligence or the ability to make decisions about where to forward data. They blindly broadcast all incoming data to all connected devices, without any awareness of the devices’ addresses or the data’s destination. Due to its broadcasting nature, a hub-based network can become inefficient and slow as the number of devices and traffic on the network grows. This inefficiency is due to the fact that devices waste resources processing data that isn’t relevant to them.
Because a hub doesn’t differentiate between devices or data types, it doesn’t provide any data segmentation. This means that sensitive data sent across a hub-based network can potentially be intercepted by any device connected to the hub.
Advantages and Disadvantages of Hub
Here are some of the advantages and disadvantages of hub mentioned –
| Advantages | Disadvantages |
| It supports various network media | Hub cannot choose the best path of the network. |
| As it is not expensive, hub can be used by anyone. | Collision detect mechanism is not included. |
| Easily connectable to various media types. | Hub does not operate in full duplex mode and it cannot be divided into the segment. |
| Hubs do not impact on the network performance. | Due to no mechanism, hub cannot reduce the network traffic. |
| Total distance of the network can be expanded. | Hub cannot filter the information as it transmits packets to all the segments that are connected. |
| It does not have the capacity to connect different network architecture like a ring, token, ethernet etc. |
Difference between Hub and Switch
Below is the table that shows the major difference between the hub and a switch –
| Hub | Switch |
| Works on the physical layer (OSI model). | Works on the data link layer (OSI model). |
| It contains a single domain of collision. | Various ports include separate collision domains. |
| Hub performs frame flooding that can broadcast, unicast or multicast. | Switch performs broadcast mainly. And also, performs unicast and multicast when needed. |
| Transmission mode is half-duplex. | Transmission mode is full-duplex. |
| Hub uses electrical signal orbits. | Switch uses frames and packets. |
| Hub does not support spanning-tree protocol. | Switch supports multiple spanning-tree. |
| Collision occurs in setup. | In full-duplex switch does not occur collisions. |
| It is a passive device. | It is a active device. |
| Does not have the ability to store MAC addresses. | Uses accessible content memory that can be accessed by application-specific integrated chips (ASIC). |
| It is not an intelligent device. | It is an intelligent device. |
| The speed of the hub network is up to 10Mb per second. | The speed of switch is 10/100 Mbps, 1Gbps, and 10Gbps. |
Read Also: OSI Model – Characteristics of Seven Layers, Why to Use & Limitations LAN (Local Area Network) – Topology, Types, Applications, Advantages
