cryptography Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adver ...

, Simultaneous Authentication of Equals (SAE) is a

password A password, sometimes called a passcode (for example in Apple devices), is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of ...

-based authentication and password-authenticated key agreement method.

Authentication

SAE is a variant of the Dragonfly Key Exchange defined in , based on Diffie–Hellman key exchange using finite cyclic groups which can be a primary cyclic group or an

elliptic curve In mathematics, an elliptic curve is a smooth, projective, algebraic curve of genus one, on which there is a specified point . An elliptic curve is defined over a field and describes points in , the Cartesian product of with itself. If ...

. The problem of using Diffie–Hellman key exchange is that it does not have an authentication mechanism. So the resulting key is influenced by a pre-shared key and the

MAC address A media access control address (MAC address) is a unique identifier assigned to a network interface controller (NIC) for use as a network address in communications within a network segment. This use is common in most IEEE 802 networking tec ...

es of both peers to solve the authentication problem.

Use

IEEE 802.11s

SAE was originally implemented for use between peers in IEEE 802.11s. When peers discover each other (and security is enabled) they take part in an SAE exchange. If SAE completes successfully, each peer knows the other party possesses the mesh password and, as a by-product of the SAE exchange, the two peers establish a cryptographically strong key. This key is used with the "Authenticated Mesh Peering Exchange" (AMPE) to establish a secure peering and derive a session key to protect mesh traffic, including routing traffic.

WPA3

In January 2018, the

Wi-Fi Alliance The Wi-Fi Alliance is a non-profit organization that owns the Wi-Fi trademark. Manufacturers may use the trademark to brand products certified for Wi-Fi interoperability. History Early 802.11 products suffered from interoperability problems be ...

announced WPA3 as a replacement to WPA2. The new standard uses 128-bit encryption in WPA3-Personal mode (192-bit in WPA3-Enterprise) and

forward secrecy In cryptography, forward secrecy (FS), also known as perfect forward secrecy (PFS), is a feature of specific key agreement protocols that gives assurances that session keys will not be compromised even if long-term secrets used in the session key ...

. The WPA3 standard also replaces the pre-shared key (PSK) exchange with Simultaneous Authentication of Equals as defined in IEEE 802.11-2016 resulting in a more secure initial key exchange in personal mode. The Wi-Fi Alliance also claims that WPA3 will mitigate security issues posed by weak passwords and simplify the process of setting up devices with no display interface.

Security

In 2019 Eyal Ronen and Mathy Vanhoef (co-author of the

KRACK KRACK ("Key Reinstallation Attack") is a replay attack (a type of exploitable flaw) on the Wi-Fi Protected Access protocol that secures Wi-Fi connections. It was discovered in 2016 by the Belgian researchers Mathy Vanhoef and Frank Piessens ...

attack) released an analysis of WPA3's Dragonfly handshake and found that "an attacker within range of a victim can still recover the password" and the bugs found "allow an adversary to impersonate any user, and thereby access the Wi-Fi network, without knowing the user's password."

Authentication

Use

IEEE 802.11s

WPA3

Security

See also

References

Further reading