About this interactive
The lesson's hub in three facts:
- **Multi-port repeater:** a repeater has a couple of ports; a hub has many. Whatever comes in on one port is repeated out every other port. It works at Layer 1 and reads no addresses.
- **Collisions:** if two devices talk at once, both signals go out the same ports and collide. Only one device can talk at a time.
- **Security:** every frame reaches every device, so any device on the hub can see the others' traffic.
Collisions grow with the number of busy devices, which is why switches replaced hubs.
What you'll learn
- Predict what a hub does with a signal: it reads no address and repeats it out every other port, like a multi-port repeater
- Predict the two problems that follow, collisions when two devices talk at once and every device receiving every frame, and why they made hubs unsuitable for modern networks
Aligned to
CompTIA Network+
1.2
Compare and contrast networking appliances, applications, and functions.
Key terms
- Ethernet Hub
- A multi-port network device that repeats any incoming signal out to all other ports, allowing computers to communicate on a network without any traffic filtering or direction.
- Collision Domain
- A network segment where data packets can collide with each other when transmitted simultaneously.
- Half Duplex
- A communication mode that allows data to be transmitted in both directions but only one direction at a time.
- Physical Layer
- Layer 1 of the OSI model, responsible for the transmission of raw bits over a physical medium.
Topics
Hub
Collisions
Collision Domain
Half Duplex
Layer 1
Interactive
Predict
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