Glossary H
DSIG

Hub

A common connection point for devices in a network. Hubs commonly are used to pass data from one device (or segment) to another.See NIST SP ...

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hacker

Hacker

Unauthorized user who attempts to or gains access to an information system. See CNSSI 4009-2015 and NIST SP 800-12 Rev. 1 under Hacker (CNSSI 4009) for more information. 

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handshake

Handshake

Protocol dialogue between two systems for identifying and authenticating themselves to each other, or for synchronizing their operations with each other. See CNSSI 4009-2015 (IETF RFC 4949 Ver 2) for more ...

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Hardening

Hardening

A process intended to eliminate a means of attack by patching vulnerabilities and turning off nonessential services. See NIST SP 800-152 for more information. 

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harm

Harm

Any adverse effects that would be experienced by an individual (i.e., that may be socially, physically, or financially damaging) or an organization if the confidentiality ...

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Hashing

Hashing

Hashing is an algorithm performed on data such as a file or message to produce a number called a hash (sometimes called a checksum). The ...

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Hash

Hash

A cryptographic hash function, such as SHA-1. See NIST SP 800-135 Rev. 1 under HASH for more information.  A function which maps strings of bits to fixed-length strings of bits, satisfying ...

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Hash Code

Hash Code

The string of bits which is the output of a hash function.See NIST SP 800-15 formore information.

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Hash-Algorithm

Hash algorithm

A sequence of steps to execute a cryptographic hash function (see Cryptographic hash function). See NIST SP 800-106 for more information. 

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Hash-message-authentication-code

HMAC

Hash- Based Message Authentication CodeKeyed-Hash Message Authentication Code specified in [FIPS198].See NIST SP 800-57 Part 1 Rev. 4 under HMAC for more information.Keyed-hash Message Authentication ...

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Hash-function

Hash Function

A function that maps a bit string of arbitrary length to a fixed length bit string and is expected to have the following three ...

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Hash-output

Hash Output

The result ofapplying a hash function to a message. Also known as a “hash value” or “hashoutput”.See CNSSI4009-2015 under message digest (NIST SP 800-107 Rev. 1) for more ...

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Hash-Value

Hash Value

The result of applying a cryptographic hash function to data (e.g., a message). Also known as a “message digest”.See NISTSP 800-106 formore information.The fixed-length bitstring produced ...

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Hashing

Hashing

The process of using a mathematical algorithm against data to produce a numeric value that is representative of that data. See the following under Hashing ...

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Health Information

Health Information

Any information, whether oral or recorded in any form or medium,that: Is created or received by a healthcare provider, health plan, public health authority, employer, ...

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HIPAA

HIPAA

Health Insurance Portability and Accountability ActThe primary law in the United States that governs the privacy of healthcare information. See NISTIR 8053 under Health Insurance Portability ...

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High Availability

High Availability

HAA failover feature to ensure availability during device or component interruptions.See NIST SP 800-113 for more information.

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High Impact

High Impact

The loss of confidentiality, integrity, or availability that could be expected to have a severe or catastrophic adverse effect on organizational operations, organizational assets, individuals, ...

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High Impact System

High Impact System

An information system in which at least one security objective (i.e., confidentiality, integrity, or availability) is assigned a FIPS Publication 199 potential impact value of ...

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Honeypot

Honeypot

A system (e.g., a webserver) or system resource (e.g., a file on a server) that is designed to beattractive to potential crackers and intruders, like ...

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Host

Host

A host is any hardware device that has the capability of permitting access to a network via a user interface, specialized software, network address, protocol ...

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Host-based IDPS

Host-based IDPS

Host-based Intrusion Detection and Prevention SystemA program that monitors the characteristics of a single host and the events occurring within that host to identify and ...

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Host Based Firewall

Host Based Firewall

Asoftware-based firewall installed on a server to monitor and control itsincoming and outgoing network traffic.See NISTSP 800-41 Rev. 1 for more information.

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Host Operating System

Host Operating System

The operating system kernel shared by multiple applications within an application virtualization architecture. See NIST SP 800-190 for more information. In a hosted virtualization solution, the OS that the ...

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Hosted Virtualization

Hosted Virtualization

A form of full virtualization where the hypervisor runs on top of a host OS. See NIST SP 800-125 for more information.

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Hot Site

Hot Site

A fully operational offsite data processing facility equipped with hardware and software, to be used in the event of an information system disruption. See  CNSSI 4009-2015 (NIST SP ...

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Hotfix

Hotfix

Updated code from Microsoft that addresses a specific security problem.  See NIST SP 800-69 for more information.  Microsoft’s term for “patch”.  See NIST SP 800-44 Version 2 for more information. 

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HTTP

HTTP

A standard method for communication between clients and Web servers. See  NISTIR 7250 and NISTIR 7387 under HyperText Transfer Protocol for more information. 

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Hybrid Cloud

Hybrid Cloud

The cloud infrastructure is a composition of two or more distinct cloud infrastructures (private, community, or public) that remain unique entities, but are bound together ...

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Hybrid Security Control

Hybrid Security Control

A security control that is implemented in an information system in part as a common control and in part as a system-specific control.  See the following  under Hybrid Security Control  for ...

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HTTPS

HTTPS

HTTP transmitted over TLS. See NIST SP 800-95 under HyperText Transfer Protocol over SSL/TLS (HTTPS) (IETF RFC 2818) for more information. 

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Hypervisor

Hypervisor

The virtualization component that manages the guest OSs on a host and controls the flow of instructions between the guest OSs and the physical hardware. See NIST ...

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