Count the Broadcast Domains

About this interactive

The lesson's rule and example: - A broadcast reaches all machines in its broadcast domain. The router does not let it extend beyond its network. - Four routers, two LANs and four WAN links between the routers make six broadcast domains: one per LAN and one per WAN link. Count the networks the routers connect: every LAN, and every link between two routers. Switches and hubs inside a LAN do not add any.

What you'll learn

Count the broadcast domains in a network with routers, LANs and WAN links
Apply the rule that a router stops broadcasts, so each network on a router port is its own broadcast domain, while switches and hubs pass broadcasts on

Aligned to

CompTIA Network+

1.6 Compare and contrast network topologies, architectures, and types.

1.2 Compare and contrast networking appliances, applications, and functions.

Cisco CCST Networking

4.4 Explain basic routing concepts

Key terms

Broadcast Domain: A network segment in which a broadcast sent by one device is received by all other devices within that segment; routers define the boundaries of broadcast domains by not forwarding broadcast traffic.
Router: A network device that forwards data packets between networks based on IP addresses.
Wide Area Network: A network that spans a large geographic area, connecting multiple local area networks.
Switch: A network device that connects devices within a LAN and forwards traffic based on MAC addresses.

Topics

Broadcast Domain Router Wan Lan Interactive Calculation

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