Authentication, Authorization, And Accounting Key (AAAK) definition in Computer Security terms:
Definition(s): Used to derive the PMK. Used with the IEEE 802.1X authentication and key management approach.
Source(s): NIST SP 800-97
Synonym(s): Master Session Key
A key shared by all parties participating in an EAP method upon a successful protocol completion. The MSK may be exported to a lower layer and transported to an authenticator. The master session key may be derived from the master key or may be the master key.
Source(s): NIST SP 800-120
reference: CSRC Glossary