The Differences between Hub, Switch, and Router
What is a Hub?
A hub is a device that connects multiple computers or other devices in a network together. It works at the physical layer of the OSI (Open Systems Interconnection) model, meaning it only sends data between devices without examining the data itself. When a device sends data to the hub, it replicates the data and sends it to all devices connected to it, regardless of whether the data is intended for that device or not. This can lead to network congestion and decreased performance, especially in large networks.
What is a Switch?
A switch also connects multiple devices in a network, but it operates at the data link layer of the OSI model, which means it examines the data packets being sent and only sends them to the intended recipient. This makes a switch more efficient than a hub, as it reduces network traffic and improves performance. Switches can also support VLANs (Virtual LANs), which allow network administrators to logically separate networks without physically separating devices.
What is a Router?
A router goes a step further than a switch by operating at the network layer of the OSI model, which means it uses IP addresses to send data packets between different networks (such as a local network and the internet). A router is designed to determine the most efficient path for a data packet to take from one network to another, which makes it an essential part of any network that needs to connect to the internet. Routers also come with security features such as firewalls, which protect the network from unauthorized access.
Conclusion
In summary, a hub, switch, and router are all devices that connect multiple devices together in a network, but they operate at different layers of the OSI model and have different functions. A hub simply replicates data to all devices, a switch examines data packets to send them to the intended recipient, and a router determines the most efficient path for data packets to take between different networks. Choosing the right device for your network will depend on your needs and the size and complexity of your network.
Table difference between hub switch and router
| Hub | Switch | Router | |
|---|---|---|---|
| Layer of the OSI model it operates on | Physical Layer (Layer 1) | Data Link Layer (Layer 2) | Network Layer (Layer 3) |
| Functionality | Passes all data received on one port to all other ports | Forwards data only to intended destination port | Routes data packets to intended destination network based on IP addresses |
| MAC address learning | No MAC address learning, flooding used instead | MAC address learning for forwarding table creation | MAC address learning for forwarding table creation and IP routing table creation |
| Collision domain | One collision domain for multiple devices | One collision domain for each port | Separate collision domain for each port |
| Extensibility | Not extendable | Can be extended with additional switch or switch stack | Can be extended with additional routing protocols and interfaces |
| Cost | Least expensive | More expensive than hub, less expensive than router | Most expensive |