[Day 12] 1. Security of WLAN and WEP

Wireless LAN (WLAN) Security

Wireless networks use radio signals, which can be intercepted by unauthorized users, making them vulnerable to attacks and eavesdropping. To mitigate these risks, implementing robust security mechanisms is essential for WLANs.

WEP (Wired Equivalent Privacy)

• WEP was the first security protocol for WLANs, designed to offer security comparable to wired networks.
• Objective: It encrypts data transmitted between devices (clients) and the access point (AP) to prevent unauthorized access and data interception.

How WEP Secures Access Points

1. Disabling ARP (Address Resolution Protocol):

   • The AP can be configured to ignore ARP requests. This prevents devices on the network from discovering the AP’s MAC address through ARP requests, adding a layer of stealth to the AP.

2. Enabling WEP on the Access Point:

   • Security is enforced by enabling WEP on the AP and setting a WEP password. This password is a shared key that must be configured on both the AP and the client devices.

3. Modified MAC Address with WEP:

   • After enabling WEP, the AP does not broadcast its raw MAC address. Instead, it uses a combination of its MAC address and the WEP password, ensuring that unauthorized users cannot access the AP without the correct credentials.

4. Client Authentication:

   • To connect to the AP, clients must:
     • Enable WEP on their devices.
     • Enter the same WEP password configured on the AP.
   • Knowing the AP’s MAC address alone is insufficient for connection without the correct WEP password.

Key Takeaways

• Shared Key System: Both the AP and clients must use the same WEP password to establish a connection.
• Connection Requirement: Without enabling WEP and entering the correct password, clients cannot communicate with the AP, even if the AP’s MAC address is known.
• Security Weakness: While WEP was a pioneering security protocol for WLANs, it is now considered outdated and insecure due to vulnerabilities that allow attackers to bypass its encryption. Modern networks should use more secure alternatives like WPA2 or WPA3.