Wireless networking encompasses more than just wireless LANs. If you're looking to become a network professional, you'll need to understand the ins and outs of wireless networks, as enterprises continue to implement them along with wired systems.
Wired connectivity is still the primary method for enterprises to configure networks, but organizations are investing more in wireless technology. According to IDC, the WLAN market increased by nearly a quarter during the first quarter of 2021. Another report from the Wireless Broadband Alliance showed enterprise interest in adopting Wi-Fi 6.
These trends indicate that network teams will regularly configure both wired and wireless networks -- a fact that Cisco has recognized in its networking certifications. Those looking to pass their Cisco Certified Technician (CCT) or Cisco Certified Network Associate (CCNA) exams will need to grasp the basics of wireless networking.
These basics include understanding the different types of wireless networks, implementing wireless standards, managing WLAN controllers and more. Glen Clarke, co-author of CCT/CCNA Routing and Switching All-in-One Exam Guide from McGraw Hill Education, dives into these topics in Chapter 15 of his book.
In this Q&A, Clarke outlines the basics of wireless networking and discusses what CCT and CCNA test-takers should prepare for when studying wireless networking.
Editor's note: The following interview was edited for length and clarity.
What should aspiring CCTs and CCNAs know about wireless networks?
Glen Clarke: The focus of wireless networking falls to the Cisco CCNA certification exam. Someone preparing for the CCT exam should know what the basics of wireless networking are, wireless standards and the role of the access point [AP] as a network device. The CCT exam does not test you on the configuration of wireless networking, while the CCNA exam does.
Someone preparing for the CCNA exam should understand wireless principles, such as the SSID [service set identifier], nonoverlapping channels and wireless encryption protocols. CCNA candidates should also understand wireless architecture components, such as APs, WLAN controllers and wireless configuration through the WLC [WLAN controller] GUI. Settings, such as creation of the WLAN, security settings and QoS [quality of service] profiles using the GUI, are required knowledge for the CCNA.
How should CCTs or CCNAs evaluate which method -- ad hoc or infrastructure -- to choose when configuring a wireless network in an enterprise?
Clarke: Ad hoc wireless networks are made up of peer-to-peer systems connecting to one another via wireless without the use of a wireless AP. Wireless networks running in infrastructure mode involve wireless clients that connect to the AP in order to connect to the network.
From an enterprise point of view, companies will almost always go with infrastructure mode, so devices are gaining network access through the AP. Enterprise networks can then build off that by using a WLAN controller to centrally manage the settings across all your APs.
What should people studying for their exams know about wireless standards? How do those standards help CCTs and CCNAs configure efficient wireless networks in enterprises?
Clarke: The CCT only covers the basics of wireless, while much of the wireless coverage is on the CCNA. For the CCNA, candidates will need to know more than just defining the wireless standards. They need to understand how to configure wireless in an enterprise environment that uses wireless APs and WLAN controllers. A CCNA professional understands the components of an enterprise wireless architecture. [They know] how to configure those components to operate in a secure manner and [how] to facilitate later changes on the network.
How should CCNAs implement wireless security protocols in their networks?
Clarke: There are several different methods to implement wireless security, depending on the scenario. For SOHO [small office/home office] networks, you can follow common best practices. First, modify the default password on the AP. Next, implement MAC [media access control] filtering to control which devices can connect to the AP. Then, implement wireless encryption -- either WPA2 [Wi-Fi Protected Access 2] or WPA3, depending on what your wireless components support. Finally, change the power level on the AP to purposely weaken the signal so that someone outside the facility cannot connect to wireless.
For larger enterprise networks, you should follow the previous list as a baseline but also implement enterprise security features, such as IEEE 802.1X, which is the use of a central authentication service, such as RADIUS [Remote Authentication Dial-In User Service] or TACACS+ [Terminal Access Controller Access Control System Plus]. A central authentication service, such as RADIUS or TACACS+, forces someone to authenticate before a connection to the wireless network is allowed.
What are some best practices for wireless security?
Clarke: There are many ways [for bad actors] to exploit security features, so high-secure environments look for more secure methods of implementing wireless. As mentioned earlier, larger enterprise networks can use RADIUS or TACACS+ as an authentication service where someone connecting to wireless must log in to the network. SOHO networks can do this as well, but it is typically seen in larger networks.
[Another option is to] treat a wireless client as a remote user -- like someone traveling on a road that needs access to the network from a hotel -- and ensure that everyone uses a VPN connection to connect to the network when using wireless. In this scenario, the user would connect to the wireless network, which does not have access to the corporate network, and then VPN into the corporate network to gain secure access to the network. This way, you're implementing the wireless network with the same level of security as a remote user coming into the network from across the internet.
How should CCNAs decide what kind of wireless architecture to set up?
Clarke: The wireless architecture used will depend on the goals of the company and the size of the company. For example, following an autonomous architecture, each AP is configured individually. So, a larger company may want to centrally manage all the APs by using a split MAC architecture where a WLAN controller is used to deploy the configuration to the APs. These APs are known as lightweight APs because they aren't configured directly, but receive their configuration from the WLC.
What is the most challenging aspect of wireless networking for CCTs and CCNAs?
Clarke: The most challenging part is getting the hands-on skills required to understand how to configure wireless in an enterprise environment using the WLAN controller. This can be a challenge because it does require getting the equipment: a WLC and multiple APs configured by the WLC.
An important tip for someone preparing for the Cisco certification exams if they do not have the equipment is to download Cisco's Packet Tracer from Cisco's network academy site. Packet Tracer is a great simulator to help someone prepare for their exams, and it contains simulated WLC and APs.