From Serebra Learning Corporation
Physical Layers 
In this module, we discuss some of the media access control (
MAC) and
Physical Layer characteristics of wireless
LANs that are common to all wireless
LAN products, regardless of the manufacturer. We also explain the difference between
Ethernet and wireless LAN frames and how wireless LANs avoid collisions.
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How Computer Protocols Work 
This
WestNet e-Learning module introduces you to the basic terms and concepts that underlie all computer communication protocols. You will learn how protocols work, and how different protocols work together to move data across a network. This knowledge will become the foundation of your understanding of how computer networks function.
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