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Computer Networks

Foundations of Networking4

Physical Layer & Signals3

Data Link Layer6

Framing techniques and CRC, the real error-detection workhorse
Frames, switches, and how a local network delivers mail
Sharing the wire without everyone talking at once
ALOHA and token passing: two more ways to share the channel
ARP, or how a device finds its neighbor's fingerprint
Bridges, and how Ethernet segments get joined without chaos

Network Layer & Routing6

Transport Layer5

Application Layer & The Web4

Wireless, Security & Performance3

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Computer Networks

Foundations of Networking4

Physical Layer & Signals3

Data Link Layer6

Framing techniques and CRC, the real error-detection workhorse
Frames, switches, and how a local network delivers mail
Sharing the wire without everyone talking at once
ALOHA and token passing: two more ways to share the channel
ARP, or how a device finds its neighbor's fingerprint
Bridges, and how Ethernet segments get joined without chaos

Network Layer & Routing6

Transport Layer5

Application Layer & The Web4

Wireless, Security & Performance3

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Framing techniques and CRC, the real error-detection workhorse

How a receiver knows exactly where one frame ends and the next begins, and the polynomial division trick (CRC) that catches errors far better than a simple checksum.

9 min readUpdated 2026-09-03computer-networksdata-link-layerframingcrcerror-detection