Wireless Communication | Set 3
Prerequisite – Wireless Communication | Set 2
Earlier, we talked about various Authentication methods. Now we talked about another aspect of wireless security, The Integrity. Integrity means the correctness of messages sent over the wireless network or the internet. Original 802.11 standard defined for the wireless network has only the WEP method for securing data send over the network.
Types of Integrity Method :
There are three integrity method : Temporal Key Integrity Protocol (TKIP), Counter CBC-MAC Protocol (CCMP), and Galois Counter Mode Protocol (GCMP). These are explained as following below.
1. Temporal Key Integrity Protocol (TKIP) –
WEP used for authentication in the security of wireless communication was later known to be vulnerable. TKIP was proposed after WEP being found vulnerable. It is designed by WiFi Alliance in 2002 and having a key-size of 128 bits. It uses the RC4 cipher algorithm for encrypting each frame.
It adds the following security features beneath underlying WEP encryption.
- Time Stamp
- TKIP Sequence Counter
- Sender’s MAC Address
- Message Integrity Check (MIC)
- Key mixing algo
TKIP was used as an Integrity method for some time until some attackers were found against it. Actually, after the revision of 802.11 standards in 2012, named 802.11-2012, TKIP is not recommended anymore.
2. Counter CBC-MAC Protocol (CCMP) –
A more secure Integrity method than TKIP was developed called Counter CBC-MAC Protocol.
It consists of two Algorithms –
- AES counter mode encryption.
- Cipher Block Chaining Message Authentication Code (CBC-MAC) for message integrity check.
Advanced Encryption Standard (AES) is the strongest encryption algorithm till date. It is widely used by security experts all over the world because it is open and publicly accessible. The only catch in implementation of CCMP is that both clients and AP must have supporting hardware. CCMP is used in the WPA2 standard used in WiFi security.
3. Galois Counter Mode Protocol (GCMP) –
Galois Counter Mode Protocol abbreviated as GCMP is most secure authentication encryption method which is more secure and efficient than CCMP.
GCMP consists of two algorithm –
- AES counter mode encryption like CCMP.
- Galois Message Authentication Code, to check the message integrity.
GCMP is used in the WPA3 standard used in WiFi security.