Glossary H
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. 

Read More

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 ...

Read More

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. 

Read More

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 ...

Read More

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 ...

Read More

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 ...

Read More

Hash Code

Hash Code

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

Read More

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. 

Read More

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 ...

Read More

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 ...

Read More

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 ...

Read More

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 ...

Read More

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, ...

Read More

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 ...

Read More

High Availability

High Availability

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

Read More

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, ...

Read More

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 ...

Read More

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 ...

Read More

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 ...

Read More

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 ...

Read More

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.

Read More

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 ...

Read More

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.

Read More

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 ...

Read More