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Protocol Overview

IEEE 802.11-2024 defines 25 Authentication and Key Management (AKM) suites that govern how stations authenticate and derive encryption keys. This section organizes them into five functional categories and links to family pages.

Authentication Categories

Every WiFi security scheme falls into one of five categories based on how the user authenticates:

Category How it works Offline crackable?
WEP Static shared key, RC4 encryption Key recovery from traffic (no password cracking)
Password (PBKDF2) Passphrase → PBKDF2 → PMK; 4-way handshake exposes MIC/PMKID Yes, dictionary/brute-force against PBKDF2
Password (SAE) Passphrase used in Dragonfly PAKE; no crackable material exposed No, online-only, rate-limited
EAP (802.1X) Credentials verified by RADIUS server via EAP method Depends on EAP inner method
Other No password (OWE), peer-to-peer (TDLS), or pre-association (PASN) No

Quick Reference

WEP (pre-AKM)

Protocol Encryption Attack Tool
WEP-40 / WEP-104 RC4 with 24-bit IV PTW key recovery (~40K ARP frames) WEPWolf / aircrack-ng

Password: PBKDF2 (offline crackable)

All six PSK families derive the PMK from a passphrase via PBKDF2-HMAC-SHA1 (4096 iterations, 256-bit output). This is the same PBKDF2 call regardless of AKM. The "SHA-256" and "SHA-384" in the AKM names refer to the post-PMK key hierarchy (KDF, MIC algorithms), not the password hashing step. Extract handshakes from pcap captures with WPAWolf and crack with hashcat.

AKM Name Variant hashcat mode Standard
WPA1 WPA-PSK Original WPA (TKIP, vendor IE 00:50:F2:01) 22000 (kv1) pre-802.11i
2 PSK WPA2-Personal (CCMP) 22000 (kv2) 802.11i-2004
4 FT-PSK Fast Transition (802.11r) 37100 (PR pending) 802.11r-2008
6 PSK-SHA256 PMF-capable (802.11w) 22000 (PMKID broken) 802.11w-2009
19 FT-PSK-SHA384 FT with SHA-384 key hierarchy none 802.11-2020
20 PSK-SHA384 SHA-384 key hierarchy with GCMP-256 none 802.11-2020

Password: SAE (not offline crackable)

These AKMs use the same passphrase but negotiate it via Dragonfly PAKE. The handshake exposes no material that can be cracked offline.

AKM Name Variant Standard
8 SAE WPA3-Personal 802.11-2012
9 FT-SAE WPA3 + Fast Transition 802.11-2012
24 SAE (group-dependent) H2E only 802.11-2024
25 FT-SAE (group-dependent) H2E + Fast Transition 802.11-2024

EAP: Enterprise (802.1X / FILS)

Authentication delegated to a RADIUS server. PMK derived from EAP Master Session Key, not a passphrase. Whether credentials are recoverable depends on the EAP inner method (e.g., PEAP/MSCHAPv2 → mode 5500; EAP-MD5 → mode 4800; EAP-TLS → not crackable).

AKM Name Variant Standard
1 802.1X Original enterprise 802.11i-2004
3 FT-802.1X Enterprise + Fast Transition 802.11r-2008
5 802.1X-SHA256 Enterprise + PMF 802.11w-2009
11 Suite B-128 (deprecated) CNSA predecessor 802.11ac-2013
12 Suite B-192 CNSA, SHA-384, P-384 certs 802.11ac-2013
13 FT-802.1X-SHA384 Suite B + Fast Transition 802.11ac-2013
14 FILS-SHA256 Fast Initial Link Setup 802.11ai-2016
15 FILS-SHA384 FILS with SHA-384 802.11ai-2016
16 FT-FILS-SHA256 FILS + Fast Transition 802.11ai-2016
17 FT-FILS-SHA384 FILS + FT + SHA-384 802.11ai-2016
22 FT-802.1X-SHA384 Enterprise FT, SHA-384 802.11-2024
23 802.1X-SHA384 Enterprise, SHA-384 802.11-2024

Other

AKM Name Purpose Standard
7 TDLS Peer-to-peer tunneled direct link 802.11z-2010
10 APPeerKey (deprecated) Removed from active standard 802.11-2012
18 OWE Opportunistic encryption, no password 802.11-2020
21 PASN Pre-association security negotiation 802.11az-2022

Full Specification Tables

Key lengths from IEEE 802.11-2024 Table 12-11 (KCK/KEK) and Table 12-8 (TK):

AKM KCK KEK TK (CCMP) TK (GCMP-256)
1, 2 128 128 128 N/A
3, 4, 5, 6 128 128 128 N/A
8, 9 (SAE) 128 128 128 N/A
11 (Suite B-128) 128 128 128 N/A
12, 13 (Suite B-192) 192 256 N/A 256
14, 16 (FILS, SHA-256) 0 (ICK=256) 256 128 N/A
15, 17 (FILS, SHA-384) 0 (ICK=384) 512 256 256
19, 20 192 256 N/A 256
22, 23 192 256 N/A 256
24, 25 group-dependent group-dependent N/A N/A

PTK derivation and MIC algorithms from IEEE 802.11-2024 Table 12-11:

AKM PTK KDF Key Descriptor Version MIC algorithm Key wrap
1, 2 PRF (HMAC-SHA1) 1 (TKIP) or 2 (CCMP) HMAC-MD5 (kv1) / HMAC-SHA1-128 (kv2) RC4 (kv1) / AES (kv2)
3, 4 (FT, SHA-256) KDF-SHA-256 3 AES-128-CMAC AES key wrap
5, 6 (SHA-256) KDF-SHA-256 3 AES-128-CMAC AES key wrap
8, 9 (SAE) KDF-SHA-256 0 (AKM-defined) AES-128-CMAC AES key wrap
11 (Suite B-128, deprecated) KDF-SHA-256 0 (AKM-defined) HMAC-SHA-256 AES key wrap
12, 13 (SHA-384) KDF-SHA-384 0 (AKM-defined) HMAC-SHA-384 AES key wrap
19, 20 (SHA-384) KDF-SHA-384 0 (AKM-defined) HMAC-SHA-384 AES key wrap
22, 23 (SHA-384) KDF-SHA-384 0 (AKM-defined) HMAC-SHA-384 AES key wrap
24, 25 (SAE-ext) group-dependent 0 (AKM-defined) group-dependent AES key wrap

Deep Dives