The company Cisco Systems itself recommends that you prepare for the 640-802 exam by seeing how you fare in the ICND1 (Interconnecting Cisco Networking Devices Part 1) and ICND2 (Interconnecting Cisco Networking Devices Part 2) v.10 courses first.
The 640-802 exam itself is considered by the company to be a composite exam which is geared for those aspiring to be experts at enterprise branch networks that are from small- to medium-sized. The specific skills which will be tested in this CCNA exam version are installation, operation, and troubleshooting of such a network.
Among the specific questions you should expect to come out in the 640-802 are: can you describe the functions of a network? Can you use interswitch communications and VLANs for configuration, verification, and troubleshooting of a particular switch? How do you meet the networking needs of an Enterprise branch network (that is medium-sized) through IP services and an IP addressing scheme? How is configuration, verification, and troubleshooting of a basic router operation, as well as routing, conducted on Cisco devices?
Other questions could be: What administrative tasks should be demanded in a WLAN? How can you determine network security risks and then eliminate or at least address those threats? As used in a medium-sized enterprise branch office networking system, how do you go about implementation, verification, and troubleshooting of ACLs and NAT? How do you go about implementation and verification of WAN links?
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