If you’re planning on taking the Security+ exam, you should have a basic understanding of primary security protocols available for wireless networks. For example, can you answer this question?
Q. You are assisting a user implement a wireless network in his home. The wireless hardware he has requires the RC4 protocol. What type of security is BEST for this network?
A. WEP
B. WPA-TKIP
C. WPA-AES
D. WPA2 Enterprise
More, do you know why the correct answer is correct and the incorrect answers are incorrect? The answer and explanation is available at the end of this post.
Because wireless networks broadcast over the air, anyone who has a wireless transceiver can intercept the transmissions. You can secure wireless networks with several different steps, but the most important step is to implement a security protocol, such as Wi-Fi Protected Access II (WPA2).
WEP as a Security Protocol
Wired Equivalent Privacy (WEP) was the original security protocol used to secure wireless networks. As the name implies, the goal was to provide the same level of privacy and security within a wireless network as you’d have in a wired network.
Unfortunately, WEP has significant vulnerabilities, and tools are widely available to break into WEP-protected networks. Due to the widely published vulnerabilities of WEP, the IEEE deprecated the use of WEP in 2004. The IEEE identified WPA as an interim replacement, and WPA2 is a permanent replacement.
WPA Replacing WEP
Wi-Fi Protected Access (WPA) was an interim replacement for WEP. It provided an immediate solution to the weaknesses of WEP without requiring users to upgrade their hardware. Even when WPA replaced WEP, its developers recognized that WPA wasn’t solid enough to last for an extended period. Instead, WPA improved wireless security by giving users an alternative to WEP with existing hardware while the developers worked on creating the stronger WPA2 protocol.
WPA2 Replacing WEP and WPA
Wi-Fi Protected Access II (WPA2) is the permanent replacement for WEP and WPA. WPA2 (also known as IEEE 802.11i) uses stronger cryptography than both WEP and WPA. The Wi-Fi Alliance requires all devices carrying its WI-FI CERTIFIED logo to meet WPA2 standards, including the use of the Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP).
Some security experts have reported cracking WPA2, though their techniques have not been freely available to the public or reviewed by peers. However, they recommend using a preshared key of at least 20 characters using a complex mix of character types to thwart the vulnerabilities they identified.
Although WPA2 provides significant security improvements over previous wireless encryption techniques, some enterprises need stronger security. Another step you can take is to enable authentication with Enterprise mode.
TKIP Versus CCMP
Temporal Key Integrity Protocol (TKIP) is an older encryption protocol used with WPA, and CCMP is a newer encryption protocol used with WPA2. IEEE has deprecated WPA and TKIP due to various security issues, but many wireless networks are still using these older protocols. IEEE recommends using WPA2 with CCMP because it provides significantly more security.
When first released, WPA used Rivest Cipher 4 (RC4) stream encryption with TKIP. WEP also uses RC4. However, TKIP does a better job of managing the encryption keys than WEP does, making it more secure. Additionally, TKIP encrypts each packet with a new key. Even though TKIP corrects several of WEP’s flaws, it was ultimately cracked.
A benefit of TKIP is that it didn’t require new hardware. WEP users could upgrade software and/or firmware and implement WPA with TKIP without the need to replace the hardware. Newer hardware supports WPA2, so the usage of WPA and TKIP is waning. However, you may still see some legacy hardware using WEP, WPA, and TKIP.
Later implementations of WPA support Advanced Encryption Standard (AES) instead of TKIP. AES is a very strong and efficient encryption algorithm. Many applications beyond WPA/WPA2 use AES to provide secure encryption and ensure confidentiality. Several people have been successful at cracking WPA with TKIP, so whenever possible, it’s best to upgrade WPA to WPA2, or at least upgrade TKIP to use AES.
WPA2 supports CCMP, which is based on AES and is much stronger than WPA using TKIP. WPA2 also employs much more secure methods of managing the encryption keys than either WEP or WPA.
Remember this
WEP has several weaknesses and should not be used. WPA provided an immediate replacement for WEP and originally used TKIP with RC4, which was compatible with older hardware. Later implementations support the stronger AES encryption algorithm. WPA2 is the permanent replacement for WEP and WPA. WPA2 supports CCMP (based on AES), which is much stronger than the older TKIP protocol.
Q. You are assisting a user implement a wireless network in his home. The wireless hardware he has requires the RC4 protocol. What type of security is BEST for this network?
A. WEP
B. WPA-TKIP
C. WPA-AES
D. WPA2 Enterprise
Answer is B. Temporal Key Integrity Protocol (TKIP) uses RC4 and is compatible with older hardware so Wi-Fi Protected Access (WPA) with TKIP is the best option for this network.
Wired Equivalent Privacy (WEP) uses RC4, but it is not secure and should not be used.
WPA with Advanced Encryption Standard (AES) is stronger, but it uses AES instead of RC4.
Wi-Fi Protected Access II (WPA2) Enterprise requires an 802.1x server and does not use RC4.