Fail closed: A control failure that result in all accesses being blocked.
Fail Open: A control failure that results in all accesses being permitted.
Failover: A failure mode in which the system automatically transfers processing to a hot backup component, such as a clustered server, if a hardware or software failure is detected.
Fail-Safe: A failure mode in which program execution is terminated, and the system is protected from compromise, if a hardware or software failure os detected.
Fail-soft (or resilient): A failure mode in which certain, noncritical processing is terminated, and the computer or the network continues to function in a degraded mode, if a hardware or software failure is detected.
False Accept Rate (FAR; or type II Error): In biometric access control systems, the percentage of unauthorized users who are incorrectly granted access. See also CER, FRR).
False Reject Rate (FRR or Type I Error):In biometric access control systems, the percentage of unauthorized users who are incorrectly denied access. See also CER, FAR).
Fault: Momentary loss of electric power.
Fault-Tolerant: A system that continues to operate after the failure of a computer or network component.
Fiber Distributed Data Interface (FDDI): A star topology, token-passing, network transport protocol.
FIPS: Federal Information Processing Standard. Standards and guidelines published by the U.S. National Institute of Standards and Technology (NIST).
Firewall: A device or program that control traffic flow between networks.
Firmware: A program or code that’s stored in ROM memory.
Forensics (or computer forensics): The science of conducting a computer crime investigation in order to determine what’s happened and who’s responsible for what’s happened. One major component of computer forensics involves collecting legally admissible evidence for use in a computer crime case.
Frame injection: An attack when the attacker is attempting to load arbitrary code into a browser in order to steal data from other frames in the browser session.
Frame Relay (FR): A packet-switched network protocol used to transport WAN communication.
Fraud: Any deceptive or misrepresented activity that result in illicit personal gain.
Fuzzy logic: An artificial intelligence method that’s used to address uncertain situations to determine whether a given condition is true or false.