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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Extending a Cisco Network to a WAN 
To describe the implementation and configuration of the different technologies used on
Cisco devices to enable wide area connections
Network administrators responsible for implementing and managing small and medium-sized business networks; network technicians who install network devices in small business environments; Cisco channel resellers who are new to Cisco products and services
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WAN Technologies 
This module reviews
WAN technologies commonly found in small to medium-size networks. Lesson 1 discusses common telecommunications and WAN terminology. Lesson 2 identifies the characteristics of High-Level Data Link Control Protocol (
HDLC) Point-to-Point
Protocol (
PPP) Integrated
Services Digital Network (
ISDN) frame relay xDSL Asynchronous Transfer Mode (ATM) and SONET. Lesson 3 discussed modem
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Point to Point Serial Connections 
This module is an overview of several
WAN technologies and how they are utilized in small- to medium-size networks. Lesson 1 discusses common telecommunications and WAN terminology. Lesson 2 begins by reviewing serial connections and the High-Level Data Link Control Protocol (
HDLC). This lesson then discusses
Point-to-Point Protocol (
PPP) an alternative that is replacing many HDLC serial
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