TKIP was created to improve wireless security on hardware built for WEP before newer protocols and hardware were available. It became part of the Wi-Fi Alliance’s first WPA certification. section 20.3.1
TKIP addresses key WEP weaknesses through several mechanisms:
- Per-packet key mixing generates a unique encryption key for every packet, making PSK brute-force attacks more difficult than with WEP’s static shared key. section 20.3.1
- A message integrity check (MIC) provides a stronger data integrity checksum than WEP’s ICV. section 20.3.1
- A sequence number is added to each frame to help prevent replay attacks, in which captured valid messages are retransmitted. section 20.3.1
TKIP remains a transitional improvement over WEP rather than the newer protection associated with WPA2 and CCMP. WPA2 uses AES-based CCMP and a stronger integrity mechanism than TKIP’s MIC. section 20.5
