pdf ccna for dummies

pdf ccna for dummies.Note: Although OTAP is not described here, you can log in at http://tinyurl.com/5hah9q.Step 3 When other APs exist and are in the Join Controller state, these APs send messages for resource management. These messages have the IP address of the controller. The AP can listen to these messages and get the IP address of the controller. The AP then sends a discovery message directly to the controller.Step 4 The next step in the process is called APpriming.AP priming often occurs after an AP is associated with at least one controller. The AP then obtains a list of other controllers from the controllers already associated with it, which lists the controllers that can be associated with the AP. These other controllers are part of a mobility group. This information is then stored in NVRAM and is available when the AP restarts. In order to contact these controllers, the AP sends a broadcast to the primary controller and all other controllers in the group.Another method of discovering controllers is through DHCP using VendorOption mode. This method uses only DHCP option 43 to get the IP address of a controller's management interface.Another method of discovering controllers is to use the Domain Name System ( DNS, DomainName System) o DHCP can be used to get IP information that includes a DNS server entry. The AP then looks up a DNS table entry for the CISCO-LWAPP-CONTROLLER, which returns the IP address of the controller's management interface. The AP can use this address to send a unicast query. This process allows an AP to discover a controller, all of which occurs in the discovery mode shown in Figure 11-2.Note: If the AP is version 12.3.11-JX1 or later, you can manually enable the AP with the console cable to bring it into the join process.11.2.3 How the LWAPPAP Selects a Controller and Joins the Controller Since this AP may join multiple controllers, it must select a controller and send a join request message to it.Figure 11-3 shows this part of the communication process. A join request message contains the following information. The type of controller.The MAC address of the controller.