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CCNA Wireless Official Exam Certification Guide part 10 is a best of breed Cisco® exam study guide that focuses specifically on the objectives for the CCNA® Wireless IUWNE exam. Senior instructor Brandon Carroll shares preparation hints and test-taking tips, helping you identify areas of weakness and improve both your conceptual knowledge and hands-on skills. Material is presented in a concise manner, focusing on increasing your understanding and retention of exam topics. | 62 CCNA Wireless Official Exam Certification Guide Outdoor Mesh Networks As you can see bridges are a good way to connect remote sites. However suppose that you are operating in a point-to-multipoint topology and the central site experiences congestion. Who suffers Just the central site Just the remote site No the answer is everyone. When two remote sites communicate through a central site the central site makes all the difference. Assume that the central site goes down as shown in Figure 4-10. Figure 4-10 Wireless Bridge Issues Now the remote sites can t communicate with each other or the central site. This can be a major issue to contend with. The solution is to deploy a mesh network such as the one illustrated in Figure 4-11. Key Topic 000000 Wireless Mesh Controller Figure 4-11 Wireless Mesh Solution Chapter 4 WLAN Technologies and Topologies 63 The mesh solution is appropriate when connectivity is important because multiple paths can be used. The IEEE is currently working on a mesh standard 802.11s . However the solution discussed here is a Cisco solution in which a wireless controller also shown in Figure 4-11 is involved. When you have a mesh network some nodes another term for APs in a mesh network are connected to a wired network. Some nodes simply act as repeaters. A mesh node repeats data to nearby nodes. More than one path is available so a special algorithm is used to determine the best path. The alternative paths can be used when there is congestion or when a wireless mesh node goes down. 64 CCNA Wireless Official Exam Certification Guide Exam Preparation Tasks Review All the Key Topics Review the most important topics from this chapter denoted with the Key Topic icon. Table 4-2 lists these key topics and the page number where you can find each one. Table 4-2 Key Topics for Chapter 4 Key Topic Item Description Page Number Figure 4-1 Wireless topology overview 52 Figure 4-2 Ad hoc network 56 Figure 4-3 Basic service area 57 Figure 4-4 Extended service
