CCNA Wireless Official Exam Certification Guide part 22 pdf

182 CCNA Wireless Official Exam Certification Guide Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-8 Cisco 4400 Series Wireless LAN Controller that can be installed in 6500 series switches or in Integrated Services Routers (ISR). There are also appliance-based controllers, which include the 44xx series WLC as well as the 2100 series WLC. Which controller you require depends on how many APs you need de- ployed. This can be anywhere from six to 300 access points per controller. This is a fixed value and can’t be upgraded via licensing. If you need to support more APs, you need an- other controller or a controller that supports more APs. The Cisco 44xx Series WLC The Cisco 44xx series Wireless LAN Controller, shown in Figure 10-8, is a standalone ap- pliance. It is designed to take up one rack unit. It has either two or four Gigabit Ethernet uplinks, and they use mini-GBIC FSG slots. It can support 12, 25, 50, or 100 APs, depending on the model. And it can support up to 5000 MAC addresses in its database. The 4400 series has a 10/100 interface called a service port; it is used for SSH and SSL connections for management purposes. The service port can be used for out-of-band man- agement, but it is not required to manage the device. You can manage the device via the controller’s logical management interface. There is also a console port that you can use to connect via HyperTerminal or Teraterm Pro. Depending on the country you are in, power requirements vary, but the chassis has two power supply slots. The controller code version used for the CCNA Wireless exam is version 5.x, and the AP runs the same version. It’s actually a requirement that they run the same version, so when an AP joins with a controller, the controller upgrades or downgrades the AP. The con- troller upgrades four APs at a time. The 4400 series can support up to 100 access points. So, a 4400 would upgrade ten APs at a time until they are all upgraded. The 3750-G WLC The 3750-G Wireless LAN Controller, shown in Figure 10-9, is integrated into a switch. There are two assemblies—the WS-C3750G-24PS-E and the AIR-WLC4402-*-K9. The two assemblies are connected to the SEPAPCB assembly, which has two Gigabit Ethernet links connecting through SFP cables and two GPIO control cables. The major benefits of this integration into the switching platform include the following: ■ Conservation of space Key Topi c 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 182 Chapter 10: Cisco Wireless Networks Architecture 183 Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-9 Cisco 3750-G Series Wireless LAN Controller ■ Integration of the backplane of the controller and switch ■ It saves ports The 3750G is stackable with the 3750G switches, so you can stack it with other 3750s that do not have the controller in them. The features it supports are the same as with the 4402 controllers; the only difference is the physical ports. The Cisco WiSM The Cisco WiSM, shown in Figure 10-10, is a services module that installs in the 6500 se- ries switch or 7600 series router with the Cisco Supervisor Engine 720. It has the same functionality as the 4400 series standalone controllers; the difference is that it supports up to 300 APs. The WiSM supports 150 access points per controller, with each blade having two controllers. Thus, you can have a total of 300 access points. You can also cluster 12 of them into a mobility domain. This allows up to 7200 lightweight APs in a mobility domain. The Cisco 2106 WLC The Cisco 2106 Wireless LAN Controller, shown in Figure 10-11, is also a single-rack unit design with eight 10/100 Ethernet ports. Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-10 Cisco WiSM 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 183 184 CCNA Wireless Official Exam Certification Guide Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-11 Cisco 2106 Series Wireless LAN Controller Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-12 Cisco WLCM It can support up to six primary access points. It has an RJ-45 console port and two RJ-45 ports that support PoE. It has nearly all the same features as the 4400 series controllers but has eight built-in switch ports. You can expect to see this controller in a small branch environment. The Cisco WLCM The Wireless LAN Controller Module (WLCM), shown in Figure 10-12, is designed for the ISR routers. You would see this controller in a small office. It has the same functionality as the 2106, but it does not have the directly connected AP and console port. It supports six APs. The WLCM-Enhanced (WLCM-E) supports eight or 12 APs, depending on which module you get. 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 184 Chapter 10: Cisco Wireless Networks Architecture 185 Of course, some limitations apply. Most of the features are similar to the 4000 series: ■ LWAPP ■ RF control ■ The ability to be a DHCP server ■ Layer 2 security The differences are things such as the following: ■ Lack of PoE ports ■ The number of APs supported ■ The LWAPP modes supported For these reasons, you see the WLCM deployed in smaller branches. Wireless LAN Controller Summary Table 10-3 summarizes the Cisco Wireless LAN Controller models. Wireless Network Management In very large networks, a single wireless controller isn’t enough to manage all your APs. This type of scenario might call for the Cisco Wireless Control System (WCS). The WCS is a single point of management for up to 3000 lightweight APs and 1250 autonomous APs. The WCS runs on a Windows or Red Hat Linux server. To scale beyond 3000 APs, you would need the WCS Navigator. The WCS Navigator enables you to navigate between different wireless control systems. It is a manager of managers, so to speak. You can use the WCS Navigator to navigate between different WCS servers. You can then scale it up to 30,000 APs in a single deployment and support up to 20 WCS deployments, all within the WCS Navigator. There is also an additional appliance you can use, called the Cisco Wireless Location Appliance, as shown in Figure 10-13. Table 10-3 Controller Summary Controller Mode Number of APs Supported Environment Deployed In 4400 Up to 100 Enterprise 3750G — Enterprise WiSM 300 per WiSM, up to 3600 Enterprise (service module) 2106 6 Branch WLCM 6 Branch 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 185 186 CCNA Wireless Official Exam Certification Guide Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-13 Cisco Location Appliance This is designed to do location tracking for Wi-Fi devices and RFID tags. It helps track thousands of devices. 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 186 Chapter 10: Cisco Wireless Networks Architecture 187 Table 10-4 Key Topics for Chapter 10 Key Topic Item Description Page Number Paragraph from the section “Features of the Cisco Controllers” Lists detailing access point and Cisco controller responsibilities 172 Figure 10-2 The CUWN architecture 175 List from the section “Access Points” Description of the two types of access points 176 Paragraphs from the section “The Cisco 44xx Series WLC” Description of the specifications and capabilities of the Cisco 44xx series WLC 182 Exam Preparation Tasks Review All the Key Topics Review the most important topics from this chapter, denoted with the Key Topic icon. Table 10-4 lists these key topics and the page number where each one can be found. Complete the Tables and Lists from Memory Print a copy of Appendix B, “Memory Tables” (found on the CD) or at least the section for this chapter, and complete the tables and lists from memory. Appendix C, “Memory Tables Answer Key,” also on the CD, includes completed tables and lists to check your work. Definition of Key Terms Define the following key terms from this chapter, and check your answers in the glossary: Lightweight AP, Autonomous AP, WLCM, WLCS References Cisco Wireless Services Module (WiSM): http://tinyurl.com/6mngkj Migrate to the Cisco Unified Wireless Network: http://tinyurl.com/5uo78w Cisco Unified Wireless Network: Secure Wireless Access for Business-Critical Mobility: http://tinyurl.com/687nff 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 187 This chapter covers the following subjects: Understanding the Different LWAPP Modes: A discussion of Layer 2 and Layer 3 LWAPP. How an LWAPP AP Discovers a Controller: A discussion regarding the process that an AP goes through when finding a controller. How an LWAPP AP Chooses a Controller and Joins It: The process an AP takes when it chooses a controller to join. How an LWAPP AP Receives Its Configuration: The process an AP takes when it retrieves its configuration. Redundancy for APs and Controllers: How to provide redundancy for your APs. The AP Is Joined, Now What?: A discussion on the different functions an AP can perform. 13_1587202115_ch11.qxp 9/29/08 2:41 PM Page 188 CHAPTER 11 Controller Discovery and Association Table 11-1 “Do I Know This Already?” Section-to-Question Mapping Foundation Topics Section Questions Understanding the Different LWAPP Modes 1–3 How an LWAPP AP Discovers a Controller 4–5 How an LWAPP AP Chooses a Controller and Joins It 6–8 How an LWAPP AP Receives Its Configuration 9 Redundancy for APs and Controllers 10–11 The AP Is Joined, Now What? 12–14 When a lightweight AP boots up, it cannot function without a controller. In this chapter, you will learn about the Lightweight Access Point Protocol (LWAPP) and the modes in which it can operate. You will also learn about how an AP finds controllers on the net- work, chooses one to join with, and then retrieves its configuration. In addition, you will look at the ways to provide redundancy for your AP in the event that a controller goes down. Finally, when an AP is joined with a controller, it can operate in certain modes that can be used for different reasons. You will learn these operational modes and when they are used. You should do the “Do I Know This Already?” quiz first. If you score 80 percent or higher, you may want to skip to the section “Exam Preparation Tasks.” If you score below 80 per- cent, you should spend the time reviewing the entire chapter. Refer to Appendix A, “An- swers to the ‘Do I Know This Already?’ Quizzes,” to confirm your answers. “Do I Know This Already?” Quiz The “Do I Know This Already?” quiz helps you determine your level of knowledge of this chapter’s topics before you begin. Table 11-1 details the major topics discussed in this chapter and their corresponding quiz questions. 1. What two modes can LWAPP operate in? (Choose two.) a. Layer 2 LWAPP mode 13_1587202115_ch11.qxp 9/29/08 2:41 PM Page 189 b. Joint LWAPP mode c. Autonomous LWAPP mode d. Layer 3 LWAPP mode 2. When LWAPP communication between the access point and the wireless LAN con- troller happens in native, Layer 2 Ethernet frames, what is this known as? a. EtherWAPP b. Hybrid mode c. Native mode LWAPP d. Layer 2 LWAPP mode 3. What is the only requirement for Layer 3 LWAPP mode? a. IP connectivity must be established between the access points and the WLC. b. You must know the IP addressing on the AP. c. Client devices must be in the same VLAN. d. Each device in the Layer 3 domain must be on the same subnet. 4. Which state is not a valid state of an AP that is discovering and joining a controller? a. Discover b. Join c. Image Data d. Hybrid-REAP 5. What is the first step in a Layer 3 LWAPP discovery? a. Priming b. AP Join Request c. Subnet broadcast of Layer 3 LWAPP discovery message d. OATAP 6. AP-Priming is used for which of the following? a. Prime an AP prior to bootup with complex algorithms b. Deliver a list of controllers to the AP using a hunting process and discovery algo- rithm c. Perform basic setup of controller configurations delivered to the AP d. Provision an AP over the air 7. Which of the following is not contained in a join response message? a. Type of controller b. Interfaces in the controller c. Number and type of radios d. AP name 190 CCNA Wireless Official Exam Certification Guide 13_1587202115_ch11.qxp 9/29/08 2:41 PM Page 190 Chapter 11: Controller Discovery and Association 191 8. The join request message is sent to the primary controller only under what condition? a. The controller is reachable. b. The AP has an IP address. c. The primary controller has low load. d. The AP is primed. 9. If no primed information is available, what does the AP look for next when trying to join a controller? a. A master controller b. A primer controller c. A new controller d. A new subnet 10. When an AP retrieves its configuration file, where is it applied? a. RAM b. ROM c. NVRAM d. Flash 11. How many backup controllers are in an N + 1 design? a. 1 b. 2 c. 3 d. 4 12. Which method is considered the most redundant? a. N + 1 b. N + N c. N + N + 1 d. N * N + 1 13. Which AP mode can you use for site surveys? a. Local mode b. H-REAP mode c. Bridge mode d. Rogue Detection mode 14. In Monitor mode, which command can you use to change the value of the channels monitored? a. config advanced channel-list b. config advanced 802.11b channel-list monitor c. config advanced 802.11b monitor channel-list d. config advanced monitor channel-list 13_1587202115_ch11.qxp 9/29/08 2:41 PM Page 191 . 182 CCNA Wireless Official Exam Certification Guide Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-8 Cisco 4400 Series Wireless LAN Controller that. 9/29/08 2:41 PM Page 183 184 CCNA Wireless Official Exam Certification Guide Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure 10-11 Cisco 2106 Series Wireless LAN Controller Courtesy. 6 Branch WLCM 6 Branch 12_1587202115_ch10.qxp 9/29/08 2:41 PM Page 185 186 CCNA Wireless Official Exam Certification Guide Courtesy of Cisco Systems, Inc. Unauthorized use not permitted. Figure