From Serebra Learning Corporation
LAN and WAN Protocols 
This
WestNet e-Learning module explores local area network (
LAN) and wide area network (
WAN) protocols and how they are used to get information into the node so it can, in turn, be delivered to the processes at the higher layers.
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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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