cyber-security-resources/SCOR/COA.md

Change of Authorization (CoA)

RADIUS Change of Authorization (CoA) is a feature that allows a RADIUS server to adjust an active client session. For instance, ISE can issue the CoA RADIUS attribute to an access device to force the session to be reauthenticated.

An example is the use of CoA when the Threat-Centric Network Access Control (TC-NAC) detects a vulnerability. The TC-NAC is a feature that enables ISE to collect threat and vulnerability data from many third-party threat and vulnerability scanners and software. The purpose of this feature is to allow ISE to have a threat and risk view into the hosts it is controlling access rights for.