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Most organizations now recognize the need to secure their Wireless Local Area Networks (WLANs). Unfortunately, many are still using outdated and insecure methods for doing so. The primary reason for its susceptibility to attacks lies in its having no physical boundaries, paving the path for illicit access and potential breaches. This guide will help you understand the risks associated with WLANs and how to secure them properly.
Wireless networks have become increasingly popular as they offer a convenient way to connect computers and other devices without the need for cumbersome cables. However, this convenience comes at a price – wireless networks are much more vulnerable to attack than their wired counterparts.
What is a WLAN?
A Wireless Local Area Network, or WLAN for short, is a network enabling computers and other devices to communicate with each other wirelessly. It uses radio waves to transmit data between devices. The WLAN provides LAN-type coverage but uses RF (usually Wi-Fi or cellular frequencies) instead of copper cable. WLANs are typically used in business settings, where the cost of wiring could be prohibitive.
Risks Associated With WLANs
One of the biggest dangers to a wireless network is its openness. Unlike wired networks, which require physical access to the network to be compromised, wireless networks can be accessed by anyone within the signal range. This makes it much easier for an attacker to gain access to your network and its data.
Another danger lies in the fact that most wireless networks are not encrypted, meaning that all data transmitted over the network is readable by anyone who intercepts it. This includes sensitive information such as credit card numbers, passwords, and confidential business data.
Even if your wireless network is encrypted, it is still possible for an attacker to gain access by using brute force methods to guess the encryption key. This is why it is important to choose a strong encryption method such as WPA2-AES and to use a long and random encryption key.
Using an older wireless standard such as WEP makes your network even more vulnerable as these encryption methods can be easily cracked by attackers. It is strongly recommended that you upgrade to a newer and more secure standard if possible.
Components of a WLAN
The essential component structure of wireless networks and standard ethernet-wired networks is the same. The hardware is relatively simple, composed of a modem or router, an access point, and network cards for each device that will be connecting to the network.
Wireless Access Points (WAPs)
These are central devices or hardware at the top of the structure of a WLAN system. The AP broadcasts the signal of a WLAN network and connects to other networks like the internet.
Wireless bridges are used to connect wireless LANs. They work as a connection between two access points (APs). They are generally used to extend the range of a wireless network.
Wireless routers are like APs. They provide LAN access to a wireless network and connect to networks like the internet.
Wireless repeaters are like wireless bridges. They are generally used to extend the range of a wireless network.
The most common wireless adapters are USB or PCI cards. Radio waves are received and transmitted via Wi-Fi adapters on computers. Most current devices include a wireless adapter.
The use of wireless controllers is necessary when there are many APs. Centralized Wi-Fi management is provided by wireless controllers, which manage all campus access points. With wireless controllers, you can centrally authenticate, control access, restrict bandwidth by group or user, prioritize traffic, and control Quality of Service (QoS).
Best Practices for Securing WLANs
There is no such thing as a one-size-fits-all solution for ensuring that devices or networks are secure. However, there are certain things we can do to help protect networks. The following are some best practices for WLAN implementations:
Each AP has a predefined default SSID value, which may identify the manufacturer and the model number. Changing SSID is a deterrent by sending out a message to attackers that the network is actively administered.
Organizations should use WPA3 Enterprise to offer centralized user authentication (e.g., RADIUS, Kerberos). They must require users to authenticate before they can access the network.
Use distinct VLANs for each user class, exactly as you would on a wired LAN.
If you must accommodate unauthenticated users (for example, guests), connect them to a VLAN outside your network's perimeter.
Install an intrusion detection system that is wireless (WIDS).
Make sure the AP is in the centre of the building to limit the distance the signal can travel (and be reachable) beyond the institution. It is possible to define a specific coverage zone with the AP.
Companies should place a firewall between the AP and the internal network in a DMZ. Before traffic reaches the wired network, let the firewall examine it.
Set up a VPN for wireless devices to use. This step adds a layer of security to data transmission.
Ensure that the access point allows known MAC addresses to connect to the network. Trusted devices should only be allowed to authenticate. This MAC address is provided in cleartext, which means an attacker may intercept it and pretend to be an authenticated device.
Perform WLAN penetration testing. Use the tools given in this section to identify AP and try to crack the current encryption method.