Switches, Hubs

“Switches” and “Hubs” are two important types of network interconnection devices, commonly used to build and manage local area networks (LANs).

 

1. What are Hubs?

Definition: A hub is a basic device used in star-topology networks, connecting multiple computers or network nodes.

Working Principles: It broadcasts received data packets to all connected devices, unable to filter or intelligently forward data, resulting in bandwidth sharing and potential efficiency loss.

Applicable Scenarios: Suitable for small networks with low data traffic.

 

2. What are Switches?

Definition: A switch is a hardware device dedicated to data forwarding, implementing filtering, learning, and forwarding tasks through hardware. It was formerly known as a bridge.

Working Principles: It intelligently identifies target devices based on MAC addresses and forwards data packets only to specific nodes, providing dedicated bandwidth and reducing network congestion.

Advantages: Compared to hubs, it significantly improves data transmission efficiency and security, making it suitable for medium-sized and larger networks.

 

3. Key Differences between Switches and Hubs

1) Bandwidth Management:

A hub uses a shared bandwidth model, with all devices competing for the same bandwidth resources.

A switch provides dedicated bandwidth, with each port independently allocated resources.

 

2) Data Filtering:

A hub cannot filter data, and its broadcasting method can easily result in redundant transmissions.

A switch uses MAC addresses for precise filtering, sending only to the intended device.

 

3) Performance Impact:

A hub’s performance significantly degrades as the number of devices increases or the amount of data increases.

A switch optimizes data transmission paths, supporting efficient scalability.

 

In summary, switches and hubs play complementary roles in network architecture, but the latter is gradually being replaced by the former due to its simplicity.