Delta PointPart of a fingerprint pattern that looks similar to the Greek letter delta (Δ), as illustrated below.
Demilitarized Zone (DMZ)A network created by connecting two firewalls. Systems that are externally accessible but need some protections are usually located on DMZ networks.
Denial of Service (DoS)The prevention of authorized access to resources or the delaying of time-critical operations.
Denial-of-service attackFlooding the networks or servers of individuals or organizations with false data requests so they are unable to respond to requests from legitimate users.
Designated Approving (Accrediting) Authority (DAA)The individual selected by an authorizing official to act on their behalf in coordinating and carrying out the necessary activities required during the…
Detection and Identification RateThe rate at which individuals, who are in a database, are properly identified in an open-set identification (watchlist) application.
Detection Error Trade-off (DET) CurveA graphical plot of measured error rates, as illustrated below. DET curves typically plot matching error rates (false non-match rate vs.
Difference ScoreA value returned by a biometric algorithm that indicates the degree of difference between a biometric sample and a reference.
Differential Power Analysis (DPA)An analysis of the variations of the electrical power consumption of a cryptographic module, using advanced statistical methods and/or other techniques…
Digital EvidenceElectronic information stored or transferred in digital form.
digital signatureThe electronic equivalent of a handwritten signature, a digital signature is a unique block of text that verifies a user's identity and is appended to a…
Disaster Recovery Plan (DRP)A written plan for processing critical applications in the event of a major hardware or software failure or destruction of facilities.
DisconnectionThe termination of an interconnection between two or more IT systems. A disconnection may be planned (e.g., due to changed business needs) or unplanned (i.
Discretionary Access ControlThe basis of this kind of security is that an individual user, or program operating on the users behalf is allowed to specify explicitly the types of…
DisruptionAn unplanned event that causes the general system or major application to be inoperable for an unacceptable length of time (e.g.
Distinguishing IdentifierInformation which unambiguously distinguishes an entity in the authentication process.
DomainA sub-network of servers and computers within a LAN. Domain information is useful when restoring backup tapes, particularly of email.
Dual-Use CertificateA certificate that is intended for use with both digital signature and data encryption services.
Due CareThe responsibility that managers and their organizations have a duty to provide for information security to ensure that the type of control, the cost of…
Duplicate Digital EvidenceA duplicate is an accurate digital reproduction of all data objects contained on the original physical item and associated media.
DurationIn simplified terms, a bond's duration measures the effect that each 1% change in interest rates will have on the bond's market value.
Easter EggHidden functionality within an application program, which becomes activated when an undocumented, and often convoluted, set of commands and keystrokes are…
EavesdroppingSurreptitiously obtaining data from an unknowing end user who is performing a legitimate function.
Education (Information Security)Education integrates all of the security skills and competencies of the various functional specialties into a common body of knowledge . . .
Egress FilteringThe process of blocking outgoing packets that use obviously false Internet Protocol (IP) addresses, such as source addresses from internal networks.
Electronic CredentialsDigital documents used in authentication that bind an identity or an attribute to a subscriber's token.
Electronic EvidenceAccording to Black's law dictionary, evidence is 'any species of proof, or probative matter, legally presented at the trial of an issue, by the act of…
Electronic Key EntryThe entry of cryptographic keys into a cryptographic module using electronic methods such as a smart card or a key-loading device.
Encrypted KeyA cryptographic key that has been encrypted using an Approved security function with a key encrypting key, a PIN, or a password in order to disguise the…
Encrypted NetworkA network on which messages are encrypted (e.g. using DES, AES, or other appropriate algorithms) to prevent reading by unauthorized parties.
EncryptionA procedure that renders the contents of a message or file unintelligible to anyone not authorized to read it.
Encryption CertificateA certificate containing a public key that is used to encrypt electronic messages, files, documents, or data transmissions, or to establish or exchange a…
End to End EncryptionCommunications encryption in which data is encrypted when being passed through a network, but routing information remains visible.
End UserA person who uses SmarterMail to send and receive mail, or to manage a domain consisting of other end user email accounts.
EnrollmentThe process of collecting a biometric sample from an end user, converting it into a biometric reference, and storing it in the biometric system's database…
EntropyA measure of the unavailable or unusable energy in a system; energy that cannot be converted to another form.
EnvironmentAll the natural and living things around us. The earth, air, weather, plants, and animals all make up our environment.
Ephemeral KeysShort-lived cryptographic keys that are statistically unique to each execution of a key establishment process and meets other requirements of the key type…
Equal Error Rate (EER)A statistic used to show biometric performance, typically when operating in the verification task.
Error Detection CodeA code computed from data and comprised of redundant bits of information designed to detect, but not correct, unintentional changes in the data.
EscrowA financial instrument held by a third party on behalf of the other two parties in a transaction.
eventIn LotusScript, an action or occurrence to which an application responds. That action can be a user-generated one, such as a mouse click; a…
ExaminationReview of a patent application to determine if a claimed invention is patentable. MPEP Introduction.
Executive AgencyAn executive department specified in 5 United States Code (U.S.C.), Sec. 101; a military department specified in 5 U.S.C., Sec.
Exploit CodeA program that allows attackers to automatically break into a system.
ExtractionThe process of converting a captured biometric sample into biometric data so that it can be compared to a reference.
Face RecognitionA biometric modality that uses an image of the visible physical structure of an individual's face for recognition purposes.
Failure to Acquire (FTA)Failure of a biometric system to capture and/or extract usable information from a biometric sample.
Failure to Enroll (FTE)Failure of a biometric system to form a proper enrollment reference for an end user.
False AcceptanceWhen a biometric system incorrectly identifies an individual or incorrectly verifies an impostor against a claimed identity
False Acceptance RateThe probability that a biometric system will incorrectly identify an individual or will fail to reject an impostor.
False Acceptance Rate (FAR)A statistic used to measure biometric performance when operating in the verification task.
False Alarm Rate (FAR)A statistic used to measure biometric performance when operating in the open-set identification (sometimes referred to as watchlist) task.
False Match RateA statistic used to measure biometric performance when. Similar to the False Acceptance Rate (FAR).
False Match Rate (FMR)Alternative to False Acceptance Rate. Used to avoid confusion in applications that reject the claimant if their biometric data matches that of an…
False Non Match Rate (FNMR)Alternative to False Rejection Rate. Used to avoid confusion in applications that reject the claimant if their biometric data matches that of an applicant.
False Non-Match RateA statistic used to measure biometric performance. Similar to the False Reject Rate (FRR), except the FRR includes the Failure To Acquire error rate and…
false positivetest result that states that an analyte is present, when, in fact, it is not present or, is present in an amount less than a threshold or designated…
False RejectionWhen a biometric system fails to identify an applicant or fails to verify the legitimate claimed identity of an applicant.
False Rejection Rate (FRR)The probability that a biometric system will fail to identify an applicant, or verify the legitimate claimed identity of an applicant.
FeatureA large, complex artifact, or part of a site, such as a hearth, cairn, housepit, rock alignment, or activity area.
Federal Bridge Certification Authority (FBCA)The Federal Bridge Certification Authority consists of a collection of Public Key Infrastructure components (Certificate Authorities, Directories…
Federal Bridge Certification Authority MembraneThe Federal Bridge Certification Authority Membrane consists of a collection of Public Key Infrastructure components including a variety of Certification…
Federal Information Processing Standard (FIPS)A standard for adoption and use by Federal agencies that has been developed within the Information Technology Laboratory and published by the National…
Federal Information SystemAn information system used or operated by an executive agency, by a contractor of an executive agency, or by another organization on behalf of an…
FERET (FacE REcognition Technology program)A face recognition development and evaluation program sponsored by the U.S. Government from 1993 through 1997. For more information visit www.frvt.
File Infector VirusA virus that attaches itself to a program file, such as a word processor, spreadsheet application, or game.
File Integrity CheckerSoftware that generates, stores, and compares message digests for files to detect changes to the files.
File Name Anomaly1) A mismatch between the internal file header and its external extension; 2) A file name inconsistent with the content of the file (e.g.
Fingerprint RecognitionA biometric modality that uses the physical structure of an individual�s fingerprint for recognition purposes.
FIPSFederal Information Processing Standards issued by the National Institute of Standards and Technology after approval by the Secretary of Commerce pursuant…
FIPS Approved Security MethodA security method (e.g., cryptographic algorithm, cryptographic key generation algorithm or key distribution technique, random number generator…
FIPS PUBAn acronym for Federal Information Processing Standards Publication. FIPS publications (PUB) are issued by NIST after approval by the Secretary of…
FirewallA set of related programs that protect the resources of a private network from users from other networks.
Firewall Control ProxyThe component that controls a firewalls handling of a call. The firewall control proxy can instruct the firewall to open specific ports that are needed by…
Firewall EnvironmentA firewall environment is a collection of systems at a point on a network that together constitute a firewall implementation.
Firewall PlatformA firewall platform is the system device upon which a firewall is implemented. An example of a firewall platform is a commercial operating system running…
Firewall RulesetA firewall ruleset is a table of instructions that the firewall uses for determining how packets should be routed between its interfaces.
FirmwareThe programs and data components of a cryptographic module that are stored in hardware within the cryptographic boundary and cannot be dynamically written…
Forensic CopyA precise bit-by-bit copy of a computer system's hard drive, including slack and unallocated space.
Forensic SpecialistA professional who locates, identifies, collects, analyzes and examines data while preserving the integrity and maintaining a strict chain of custody of…
Forensics, ComputerThe practice of gathering, retaining, and analyzing computer-related data for investigative purposes in a manner that maintains the integrity of the data.
Formatting FunctionThe function that transforms the payload, associated data, and nonce into a sequence of complete blocks.
Forward CipherOne of the two functions of the block cipher algorithm that is determined by the choice of a cryptographic key.
FRGC (Face Recognition Grand Challenge)A face recognition development program sponsored by the U.S. Government from 2003-2005. For more information visit www.frvt.org/FRGC. See also FERET, FRVT.