Difference between Hub and Bridge

A hub and a bridge are both devices used to connect computers and other devices in a network, but they work in different ways. A hub is a simple device that sends the same data to all devices connected to it. A bridge is smarter, it looks at the data and sends it only to the correct device or network segment.

What is Hub?

Hub is a networking device that is used to transmit the signal to each port (except one port) to respond from which the signal was received. Hub is operated on the Physical layer. In this packet filtering is not available. It is of two types: Active Hub, Passive Hub. 

Types of Network Hub

Networks hubs are classified into three types:

1. Active Hub: They have a power supply for regenerating, and amplifying the signals. When a port sends weak signalled data, the hub regenerates the signal and strengthens it, then send it further to all other ports. Active hubs are expensive in costs as compared to passive hubs.

2. Passive Hub: Passive hubs are simply used to connect signals from different network cables as they do not have any computerised element. They simply connect the wires of different devices in the star topology. Passive hubs do not do any processing or signal regeneration and that’s why do not require electricity the most they can do is they can copy or repeat the signal. It can’t clean the message, and it can’t amplify or strengthen the signal.

3. Intelligent Hub: Intelligent hubs as the name suggests are smarter than active and passive hubs. The intelligent hub comprises a special monitoring unit named a Management Information Base (MIB). This is software that helps in analysing and troubleshooting network problems. Intelligent hubs work similarly to active hubs but with some management features. Like it can monitor the traffic of the network and the configuration of a port.

Features of Hub

• Operates at the physical layer of the network, dealing only with signals.
• Broadcasts data to all connected devices, without checking where the data should go.
• Simple design, no filtering of data.
• Supports half-duplex.

How Does a Network Hub Work?

A hub is a multiport device, which has multiple ports in a device and shares the data to multiple ports altogether. A hub acts as a dumb switch that does not know, which data needs to be forwarded where so it broadcasts or sends the data to each port.

Suppose there are five ports in a hub A, B, C, D, and E. Consider A wants to send any data frame, or let’s say A is acting as a sender, so the hub will forward the data transmitted by A to B, C, D, E. Now, at the same time B also wants to send the data then data received from A and B will collide and can cause data loss. In this situation, the data gets destroyed, and the hosts send a jam signal to all the hosts informing them about the collision, and each sender needs to wait for a certain amount of time.

Use Cases of Hub

Below are the use cases of Hub:

• Best for small networks, such as home networks, where traffic is low.
• Useful for temporary network setups, like during meetings or events.

What is Bridge?

Bridge is also a network device that is used to connect two different LANs working on the same protocol. Types of the bridge are Source route, Transparent, and Translation. In bridge one port for incoming and another port for outgoing. 

Types of Bridges

There are three types of bridges in computer networks, which are as follows:

1. Transparent Bridge: Transparent bridges are invisible to other devices on the network. This bridge doesn’t reconfigure the network on the addition or deletion of any station. The prime function of the transparent bridge is to block or forward the data according to the MAC address.
2. Source Routing Bridge: Source routing bridges were developed and designed by IBM specifically for token ring networks. The frame’s entire route is embedded with the data frames by the source station to perform the routing operation so that once the frame is forwarded it must follow a specific defined path/route.
3. Translational Bridge: Translational bridges convert the received data from one networking system to another. Or it is used to communicate or transmit data between two different types of networking systems. Like if we are sending data from a token ring to an Ethernet cable, the translational cable will be used to connect both the networking system and transmit data.

Features of Bridge

• Works at the data link layer, managing data more intelligently.
• Supports full-duplex, allowing data to be sent and received at the same time.
• Segments the network, reducing data traffic.

Working of Bridges

Let’s see the step-by-step working of the bridge in computer networks:

1. Receiving Data: The bridge gets data packets (or frames) from both network segments A and B.
2. Building a Table: It creates a table of MAC addresses by looking at where the data is coming from to know which device is on which segment.
3. Filtering Data: If the data from network A is meant for a device also on network A, the bridge stops it from going further.
4. Forwarding Data: If the data from network A is meant for a device on network B, the bridge sends it to the correct place on network B.
5. Repeating for Both Sides: The bridge does the same thing for data coming from network B.

Use Cases of Bridge

Below are the use cases of Bridge:

• Used in larger networks to reduce traffic and improve efficiency.
• Can be used to connect two different types of networks.

Difference between Hub and Bridge

Conclusion

In conclusion, hubs are simple devices best for small networks, while bridges are more advanced, improving network efficiency by controlling traffic. If you need basic connectivity, a hub may work fine. But for larger, more complex networks, a bridge is a better choice to reduce congestion and ensure better performance.