The key difference between hub and bridge is that hub works on the physical layer, but bridge runs on the data link layer of OSI model. Hubs and bridges have different uses. Hubs send data to each device connected to them, and it broadcasts data. On the other hand, the bridge is more intelligent, checking and filtering data before forwarding data. This mechanism can significantly reduce network traffic and improve security.
Hubs can connect two LAN segments, while bridges can connect two different LANs.
Differences between Hubs and Bridges
|BASIS FOR COMPARISON||HUB||BRIDGE|
|Basics||Used to connect a number of devices.||Facilitates in the segmentation of the larger network.|
|Types||Active and Passive||Transparent, translational and source route.|
|Data filteration||Not performed||Conducted|
|Uses||Multiple ports||Single incoming and outgoing port|
|Links||Segments of LAN||Two different LAN employing same protocol.|
What is the hub?
Hub is a basic network device because it provides a very simple function of establishing connections between several devices. In addition, the device can also be used as a connector for different LAN segments. These devices are connected to the hub by twisted pair cables. The main purpose of hubs is to transmit data packets to each device connected to them.
It does not perform any filtering, which means that each block of data is transmitted to all connected terminal devices, even if it is not the target device. That's why it's considered a non-intelligent device. Hubs work in a single conflict area, which means that transmission lines should run at the same speed.
What is the bridge?
A bridge is also a network device that connects two different LANs running on the same protocol. In addition, it is used to segment larger LANs into smaller networks. When the bridge receives a frame from the network, it retrieves the target address from its head and checks it in the table to find the location of the transmitted frame. Unlike hubs, in bridges, different lines can have their own conflict domains.
Ethernet can't process token ring frames, the reason behind it is that it can't find and retrieve the target address in the header. However, the bridge can use the circuit card for different network types and variable speeds.
It has been mentioned that bridges can also divide larger networks into smaller ones, but how can they do that? The bridge is located between two physical segments and monitors the data flow between the two segments. Here, MAC addresses play an important role in deciding whether data should be forwarded or discarded according to conditions.
Early bridges used to create a list of MAC addresses manually. In modern bridges, this task is automatically accomplished by observing traffic on the network. These bridges are called learning bridges.
Main differences between hub and Bridge
- Hubs are used as central devices to provide connections between nodes. Instead, bridges are used to filter and forward data in networks.
- There are two types of hubs - active and passive. There are three types of bridges: transparent, translational and source routes.
- Data filtering is performed in bridges rather than hubs.
- Hubs use multiple ports, while bridges use a single incoming and outgoing port to store specific data.
There are basically two types of hubs, active hubs and passive hubs.
Passive Hub - Passive hubs provide only channels for the transmission of electrical signals.
Active Hub - In an Active Hub, it not only provides a channel for electrical signals, but also regenerates signals before they are transmitted to other connected devices. However, it does not process any data.
Types of bridges
Transparent Bridges - This type of bridge is hidden from other devices on the network, and other devices do not know the existence of these bridges. Transparent bridges block and forward data mainly according to MAC addresses.
Source Routing Bridge - Source Routing Bridge is used by Token Ring Network. These bridges contain frame and routing information, which helps to make decisions for frame forwarding over the network.
Conversion Bridges - These types of bridges can convert network system types to link two different networks, such as Ethernet and token ring networks. The conversion bridge can change the information and fields in the frame, and ultimately convert the data it receives.
Network device hubs and bridges are designed to perform different functions, in which hubs are used as connectors for LAN segments. On the other hand, bridges are used to connect two different LANs.