Cisco Systems CCNA 2 manual Introduction to WANs, Introduction to routers in a WAN

1.1 WANs

Essential labs:	None
Optional labs:	None
Core TIs:	All
Optional TIs:	none

Course-level claim: Students can identify the important characteristics of common WAN configurations and technologies, differentiate between these and common LAN technologies, and describe the role of a router in a WAN.

Certification-level claim: Students can evaluate the important characteristics of WANs and implement simple WAN protocols.

Hands-on skills: none

1.1.1 Introduction to WANs

WANs differ from LANs in several ways:

•LANs connect workstations, peripherals, terminals, and other devices in a single building or several buildings that are located next to each other, and WANs connect large geographic areas.

•LANs connect devices and WANs connect data connections across a broad geographic area.

WANs operate at the physical and data-link layers of the OSI model. Devices used in a WAN are routers, switches, modems, and communication servers. The following topics are relevant to this TI:

•Discuss the various carriers and devices available for WAN connections.

•Show students what routers in a WAN look like.

•Explain what routers do.

Figure 3 is an important figure to review. Best instructional practices for this TI include online study sessions with study guides, group work, and mini-lectures. This TI provides essential background information for the CCNA exam.

1.1.2 Introduction to routers in a WAN

Routers and computers have four basic common components:

•CPU

•Bus

11 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Module 1 Copyright ♥ 2004, Cisco Systems, Inc.