About this interactive
How the lesson counts:
- A **bridge** between two hubs makes two collision domains, one each side.
- **Three hubs** on a switch make three: one per hub, because collisions can happen on each hub.
- A **switch** with six devices on six ports makes six: a switch does not let collisions cross between ports.
The rule: hubs and repeaters join everything on them into one collision domain; each bridge, switch or router port is its own. Count the switch and router ports in use, treating a hub (with everything on it) as one.
What you'll learn
- Count the collision domains in a network built from hubs, repeaters, bridges, switches and routers
- Apply the rule: everything joined through hubs and repeaters shares one collision domain, and every bridge, switch or router port starts a new one
Aligned to
CompTIA Network+
1.2
Compare and contrast networking appliances, applications, and functions.
Cisco CCNA
1.13
Describe switching concepts
Cisco CCST Networking
4.5
Explain basic switching concepts
Key terms
- Collision Domain
- A network segment where data packets can collide with each other when transmitted simultaneously.
- Hub
- A basic Layer 1 network device that receives a signal on one port and repeats it out every other port simultaneously, creating a single shared collision domain among all connected devices. Hubs have been replaced by switches in modern networks because they waste bandwidth and cause collisions.
- Bridge
- A network device that connects two or more network segments and filters traffic based on MAC addresses.
- Switch
- A network device that connects devices within a LAN and forwards traffic based on MAC addresses.
Topics
Collision Domain
Hub
Bridge
Switch
Interactive
Calculation
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