About this interactive
The lesson's trip:
- The laptop's traffic goes to its router.
- The router reads the Layer 3 information (the destination IP address) to work out which direction to send it.
- It has several options and chooses the one it judges best, then forwards the packet that way.
- The next router does the same thing.
- The router attached to the destination's network sends it to the end device.
Because every decision is made from Layer 3 information, a router is a Layer 3 device.
What you'll learn
- Put in order how routers carry a packet across several networks: each router reads the destination IP address, chooses the best path and forwards the packet, until the router attached to the destination network delivers it
- Explain why a router is a Layer 3 device: it decides from the Layer 3 (IP) information in the packet
Aligned to
CompTIA Network+
1.2
Compare and contrast networking appliances, applications, and functions.
2.1
Explain characteristics of routing technologies.
Key terms
- Router
- A network device that forwards data packets between networks based on IP addresses.
- Packet
- A unit of data formatted for transmission over a network, containing a header, payload, and sometimes a trailer.
- IP Address
- A numerical label assigned to each device connected to a network that uses the Internet Protocol.
- Layer 3
- The Network layer of the OSI model, responsible for logical addressing and routing packets between networks.
Topics
Router
Routing
Layer 3
Packet
Interactive
Ordering
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