Glossary of Terms Flashcards
32-bit versus 64-bit
Processing modes referring to the size of each instruction processed by the CPU. 320bit CPU’s replaced earlier 16-bit CPU’s and were used through the 1990s to the present day, through most PC and laptop CPUs now work in 640bit mode. The main 64-bit platform is called AMD64 or EM64T (by Intel). Software can be compiled as 32-bit or 64-bit. 64 bit CPUs can run most 32-bit software, but a 32-bit CPU can’t execute 64-bit software.
3D Printer
Hardware device capable of small-scale manufacturing. Most 3D printers use either a variety of filament (typically plastic) or resin media with different properties.
802.11 Standards
Specifications developed by IEEE for wireless networking over microwave radio transmission in the 2.4 GHz, 5 GHz, and 6 GHz frequency bands. The Wi-Fi standards brand has six main iterations: a, b, g, Wi-Fi 4 (n), Wi-Fi 5 (ac), and Wi-Fi 6 (ax). These specify different modulation techniques, supported distances, and data rates, plus special features, such as channel bonding, MIMO, and MU-MIMO.
802.3 Ethernet
Standards developed as the IEEE 802.3 series describing media types, access methods, data rates, and distance limitations at OSI Layers 1 and 2 using xBASE-y designations.
Access Point (AP)
Device that provides a connection between wireless devices and can connect to wired networks, implementing an infrastructure mode WLAN.
Adapter Cable
Peripheral cable converting between connector form factors or between signaling types, such as DisplayPort to HDMI.
Advanced Micro Devices (AMD)
CPU manufacturer providing healthy competition for Intel. AMD chips such as the K6 or Athlon 64 and latterly the Ryzen have been very popular with computer manufacturers and have often out-performed their Intel equivalents.
Advanced RISC Machines (ARM)
Designer of CPU and chipset architectures widely used in mobile devices. RISC stands for reduced instruction set computing. RISC microarchitectures use a small number of simple instructions that can be performed as a single operation. This contrasts with complex (CISC) microarchitectures, which use a large set of more powerful instructions that can take more than one operation to complete.
advanced technology extended (ATX)
Standard PC case, motherboard, and power supply specification. Mini-, Micro-, and Flex-ATX specify smaller board designs.
airplane mode
A toggle found on mobile devices enabling the user to disable and enable wireless functionality quickly.
App Store
Feature of mobile computing that provides a managed interface for installing third-party software apps.
Application Programming Interface (API)
Library of programming utilities used, for example, to enable software developers to access functions of the TCP/IP network stack under a particular operating system.
Application Virtualization
Software delivery model where the code runs on a server and is streamed to a client.
Authentication, Authorization, and Accounting (AAA)
Security concept where a centralized platform verifies subject identification, ensures the subject is assigned relevant permissions, and then logs these actions to create an audit trail.
Automatic Document Feeder (ADF)
Device that feeds media automatically into a scanner or printer.
Automatic Private IP Addressing (APIPA)
Mechanism for Windows hosts configured to obtain an address automatically that cannot contact a DHCP server to revert to using an address from the range 169.254.x.y. This is also called a link-local address.
Backlight
LED or fluorescent lamp that illuminates the image on a flat-panel (TFT) screen. If the backlight component fails, only a dim image will be shown.
Basic Input/Output System (BIOS)
Legacy 32-bit firmware type that initializes hardware and provides a system setup interface for configuring boot devices and other hardware settings.
Basic Service Set ID (BSSID)
MAC address of an access point supporting a basic service area.
Battery
Power source for a portable computer, typically a rechargeable Lithium-ion (Li-ion) type. A small coin cell battery is also used in a computer to power CMOS RAM.
Beep Codes
During POST, errors in hardware or the system firmware data can be brought to the attention of the user by beep noises. Each beep code is able to draw attention to a particular fault with the hardware. It was once customary for a computer to beep once to indicate that POST has been successful, though most modern computers boot silently.
Binary
Notational system with two values per digit (zero and one). Computers process code in binary because the transistors in its CPU and memory components also have two states (off and on).
Biometric Authentication
Authentication mechanism that allows a user to perform a biometric scan to operate an entry or access system. Physical characteristics stored as a digital data template can be used to authenticate a user. Typical features used include facial pattern, iris, retina, fingerprint pattern, and signature recognition.
Blue Screen of Death (BSOD)
Microsoft status screen that indicates an error from which the system cannot recover (also called a stop error). Blue screens are usually caused by bad driver software or hardware faults (memory or disk). Other operating systems use similar crash indicators, such as Apple’s pinwheel and Linux’s kernel panic message.
Bluetooth
Short-range, wireless radio-network-transmission medium normally used to connect two personal devices, such as a mobile phone and a wireless headset.
Blu-ray Disc
Latest generation of optical drive technology, with disc capacity of 25 GB per layer. Transfer rates are measured in multiples of 36 MB/s.
Boot Options
Disk or network adapter device from which an operating system can be loaded.
Boot Password
Feature of system setup that prevents the computer from booting until the correct user password is supplied. A supervisor password restricts access to the system setup program.
Bus
Connections between components on the motherboard and peripheral devices providing data pathways, memory addressing, power supply, timing, and connector/port form factor.
Cable Modem
Cable-Internet-access digital modem that uses a coaxial connection to the service provider’s fiber-optic core network.
Cable Stripper
Tool for stripping cable jacket or wire insulation.
Cable Tester
Two-part tool used to test successful termination of copper cable by attaching to each end of a cable and energizing each wire conductor in turn with an LED to indicate an end-to-end connection.
Capture Card
Adapter card designed to record video from a source such as a TV tuner or games console.
Carriage Belt
Inkjet print device component that moves the print head over the paper.
Cellular Radio
Standards for implementing data access over cellular networks are implemented as successive generations. For 2G (up to about 48 Kb/s) and 3G (up to about 42 Mb/s), there are competing GSM and CDMA provider networks. Standards for 4G (up to about 90 Mb/s) and 5G (up to about 300 Mb/s) are developed under converged LTE standards.
Central Processing Unit (CPU)
Principal microprocessor in a PC or mobile device responsible for running firmware, operating system, and applications software.
Certificate
Issued by a Certificate Authority (CA) as a guarantee that a public key it has issued to an organization to encrypt messages sent to it genuinely belongs to that organization.
Certificate Authority (CA)
Server that guarantees subject identities by issuing signed digital certificate wrappers for their public keys.
Channel
Subdivision of frequency bands used by Wi-Fi products into smaller channels to allow multiple networks to operate at the same location without interfering with one another.
Channel Bonding
Capability to aggregate one or more adjacent wireless channels to increase bandwidth.
Chipset
Processors embedded on a motherboard to support the operation of the CPU and implementing various controllers (for memory, graphics, I/O, and so on).
Clock
System clock signal that synchronizes the operation of all of the components within a PC. It also provides the basic timing signal for the processor, bus, and memory. The CPU typically runs at many multiples of the basic clock speed
Cloud Computing
Computing architecture where on-demand resources provisioned with the attributes of high availability, scalability, and elasticity are billed to customers on the basis of metered utilization.
Cloud Servicing Model
Classifying the provision of cloud services and the limit of the cloud service provider’s responsibility as software, platform, infrastructure, and so on.
Cloud Service Provider (CSP)
Organization providing infrastructure, application, and/or storage services via an “as a service” subscription-based, cloud-centric offering.
Coaxial Cable
Media type using two separate conductors that share a common axis categorized using the Radio Grade (RG) specifications.
Code Division Multiple Access (CDMA)
Method of multiplexing a communications channel using a code to key the modulation of a particular signal. CDMA is associated with Sprint and Verizon cellular phone networks.
Collision Domain
Network segment where nodes are attached to the same shared access media, such as a bus network or Ethernet hub.
Community cloud
Cloud that is deployed for shared use by cooperating tenants.
Compact Disc (CD)
Optical storage technology supporting up to 700 MB per disc with recordable and re-writable media also available.
Containerization
Type of virtualization applied by a host operating system to provision an isolated execution environment for an application.
Crimped
Tool to join a Registered Jack (RJ) form factor connector to the ends of twisted-pair patch cable.
Cyan, Magenta, Yellow, Black (CMYK)
Subtractive color model used by print devices. CMYK printing involves use of halftone screens. Four screens (or layers) of dots printed in each of the colors are overlaid. The size and density of the dots on each layer produce different shades of color and is viewed as a continuous tone image.
Data Cap
Feature of mobile computing that allows use of a network connection to be limited to avoid incurring additional carrier charges.
Data Loss (leak) Prevention (DLP)
Software solution that detects and prevents sensitive information from being stored on unauthorized systems or transmitted over unauthorized networks.
Data Center
Facility dedicated to the provisioning of reliable power, environmental controls, and network fabric to server computers.
DDR SDRAM (Double Data Rate SDRAM)
Series of high-bandwidth system-memory standards (DDR3/DDR4/DDR5) where data is transferred twice per clock cycle.
Decibel (dB)
Unit for representing the power of network signaling.
decibels per isotopic (dBi)
Unit for representing the increase in power gained by the directional design of a wireless antenna.
Default Gateway
IP configuration parameter that identifies the address of a router on the local subnet that the host can use to contact other networks.
Desktop as a Service
Cloud service model that provisions desktop OS and applications software.
Digital Camera
Version of a 35 mm film camera where the film is replaced by light-sensitive diodes and electronic storage media (typically a flash memory card). The sensitivity of the array determines the maximum resolution of the image, measured in megapixels. Most mobile devices are fitted with embedded cameras that can function as both still and video cameras.
Digital Subscriber Line (DSL)
Carrier technology to implement broadband Internet access for subscribers by transferring data over voice-grade telephone lines. There are various “flavors” of DSL, notably S(ymmetric)DSL, A(symmetric)DSL, and V(ery HIgh Bit Rate)DSL.
Digital Video Interface (DVI)
Legacy video interface that supports digital only or digital and analog signaling.
Digital Video/Versatile Disk (DVD)
Optical storage technology supporting up to 4.7 GB per layer per disc with recordable and re-writable media also available.
Digitizer
As part of a touch screen assembly, the digitizer is a touch-sensitive layer placed on top of the display panel. The digitizer converts analog touch and gesture events to digital signals that can be interpreted as different types of input.
Direct Burial
A type of outside plant (OSP) installation where cable is laid directly into the ground with no protective conduit.
DisplayPort
Digital audio/video interface developed by VESA. DisplayPort supports some cross-compatibility with DVI and HDMI devices.
Docking Station
Advanced type of port replicator designed to provide additional ports (such as network or USB) and functionality (such as expansion slots and drives) to a portable computer when used at a desk.
Domain Name System (DNS)
Service that maps fully qualified domain name labels to IP addresses on most TCP/IP networks, including the Internet.
Domain-Based Message Authentication, Reporting and Conformance (DMARC)
Framework for ensuring proper application of SPF and DKIM utilizing a policy published as a DNS record.
DomainKeys Identified Mail (DKIM)
Cryptographic authentication mechanism for mail utilizing a public key published as a DNS record.
D-subminiature Shell Connector (DB-9)
Legacy connector form factor used for serial (9-pin) and VGA (15-pin) interfaces.
Dual Inline Memory Module
Standard form factor for system memory. There are different pin configurations for different DDR-SDRAM RAM types.
Dual-Channel
System-memory controller configuration that provides two data pathways between the memory modules and a compatible CPU.
Duplex Unit
Installable option that enables a print device or scanner to use both sides of a page automatically.
Dynamic Frequency Selection (DFS)
Regulatory feature of wireless access points that prevents use of certain 5 GHz channels when in range of a facility that uses radar.
Dynamic Host Configuration Protocol (DHCP)
Protocol used to automatically assign IP addressing information to hosts that have not been configured manually.
Effective Isotropic Radiated Power (EIRP)
Signal strength from a transmitter, measured as the sum of transmit power, antenna cable/connector loss, and antenna gain.
Elasticity
Property by which a computing environment can add or remove resources in response to increasing and decreasing demands in workload.
Electrostatic Discharge (ESD)
Metal and plastic surfaces can allow a charge to build up. This can discharge if a potential difference is formed between the charged object and an oppositely charged conductive object. This electrical discharge can damage silicon chips and computer components if they are exposed to it.
Electronic store and forward messaging system. Email supports text messages and binary file attachments. For Internet email, an SMTP (Simple Mail Transfer Protocol) server is used to forward mail to a host. A mail client then uses either POP3 (Post Office Protocol) or IMAP (Internet Mail Access Protocol) to access the mailbox on the server and download messages.
Embedded System
Electronic system that is designed to perform a specific, dedicated function, such as a microcontroller in a medical drip or components in a control system managing a water treatment plant.
Enclosure
Chassis for connecting an internal disk unit as an external peripheral device.
End of Life (EOL)
Product life cycle phase where mainstream vendor support is no longer available.
Error Correction Code (ECC)
System memory (RAM) with built-in error correction security. It is more expensive than normal memory and requires motherboard support. It is typically only used in servers.
Escalation
In the context of support procedures, incident response, and breach-reporting, escalation is the process of involving expert and senior staff to assist in problem management.
External Serial Advanced Technology Attachment (eSATA)
Variant of SATA cabling designed for external connectivity.
Fan
Cooling device fitted to PC cases and components to improve air flow.
Fiber Optic Cable
Network cable type that uses light signals as the basis for data transmission. Infrared light pulses are transmitted down the glass core of the fiber. The cladding that surrounds this core reflects light back to ensure transmission efficiency. Two main categories of fiber are available; multi-mode, which uses cheaper, shorter wavelength LEDs or VCSEL diodes, or single-mode, which uses more expensive, longer wavelength laser diodes. At the receiving end of the cable, light-sensitive diodes re-convert the light pulse into an electrical signal. Fiber optic cable is immune to eavesdropping and EMI, has low attenuation, supports rates of 10 Gb/s+, and is light and compact.
Fiber to Premise (FTTP)
Internet connection type that uses a fiber link between the subscriber premises and ISP network. Fiber to the premises (FTTP) uses a full fiber link, while fiber to the curb (FTTC) retains a short segment of copper wire between the subscriber premises and a street cabinet.
Filament
3-D print device media type.
File Server
In file server–based networks, a central machine provides dedicated file and print services to workstations. Benefits of server-based networks include ease of administration through centralization.
File Transfer Protocol (FTP)
Application protocol used to transfer files between network hosts. Variants include S(ecure)FTP, FTP with SSL (FTPS and FTPES) and T(rivial)FTP. FTP utilizes ports 20 and 21.
Finisher Unit
Print device component used to automate document production, such as hole punching or stapling print jobs.
Firewall
Software or hardware device that protects a network segment or individual host by filtering packets to an access control list.
Firmware
Software instructions embedded on a hardware device such as a computer motherboard. Modern types of firmware are stored in flash memory and can be updated more easily than legacy programmable read-only memory (ROM) types.
Flash Drive
Solid state flash memory provisioned as a peripheral device with a USB interface.
Flatbed Scanner
Type of scanner where the object is placed on a glass faceplate and the scan head moves underneath it.
Form Factor
Size and shape of a component, determining its compatibility. Form factor is most closely associated with PC motherboard, case, and power supply designs.
Frequency Band
Portion of the microwave radio-frequency spectrum in which wireless products operate, such as 2.4 GHz band or 5 GHz band.
F-Type Connector
Screw down connector used with coaxial cable.
Fully Qualified Domain Name (FQDN)
Unique label specified in a DNS hierarchy to identify a particular host within a subdomain within a top-level domain.
Fused
Assembly in a laser print device that fixes toner to media. This is typically a combination of a heat and pressure roller.
Global Positioning System (GPS)
Means of determining a receiver’s position on Earth based on information received from orbital satellites.
Global System for Mobile Communication (GSM)
Standard for cellular radio communications and data transfer. GSM phones use a SIM card to identify the subscriber and network provider. 4G and later data standards are developed for GSM.
Google Workspace
Mobile/cloud computing office productivity and data storage suite operated by Google.
Hard Disk Drive (HDD)
Mass storage device that uses mechanical platters with a magnetic coating that are spun under disk heads that can read and write to locations on each platter (sectors).
Hardware Security Module (HSM)
An appliance for generating and storing cryptographic keys. This sort of solution may be less susceptible to tampering and insider threats than software-based storage.
Header (Motherboard)
Connector on the motherboard for internal cabling, such as fan power and front panel ports and buttons.
Headset
Peripheral device supporting audio input (microphone) and output (speaker headphones).
Heat Sink
Cooling device fitted to PC components to optimize heat transfer.
High Availability (HA)
Metric that defines how closely systems approach the goal of providing data availability 100% of the time while maintaining a high level of system performance.
High-Definition Multimedia Interface (HDMI)
Digital audio/video interface developed for use on both consumer electronics and computer equipment.
Hotspot
Using the cellular data plan of a mobile device to provide Internet access to a laptop or PC. The PC can be tethered to the mobile by USB, Bluetooth, or Wi-Fi (a mobile hotspot).
Hub
Layer 1 (Physical) network device used to implement a star network topology on legacy Ethernet networks, working as a multiport repeater.
Hybrid Cloud
Cloud deployment that uses both private and public elements.
HyperText Transfer Protocol/HTTP Secure
Application protocol used to provide web content to browsers. HTTP uses port 80. HTTPS(ecure) provides for encrypted transfers, using TLS and port 443.
iCloud
Mobile/cloud computing office-productivity and data-storage suite operated by Apple and closely integrated with macOS and iOS.
Image
Clone copy of an operating system installation (including installed software, settings, and user data) stored as a file on disk. VMs use images to store persistent data, and the technology is also used to make system backups.
Imaging Drum
Drum or belt in a laser printer that supports a high electric charge that can be selectively removed using a laser or LED light source.
Impact Printer
Typically a dot matrix printer, this uses pressure to transfer ink from a ribbon onto paper in a particular pattern, similar to the mechanism of a typewriter.
Indoor Positioning System (IPS)
Technology that can derive a device’s location when indoors by triangulating its proximity to radio sources such as Bluetooth beacons or Wi-Fi access points.
Information Technology Extended (ITX)
Series of motherboard form factors designed for small form factor (SFF) computers and appliances.
Infrastructure as a Service (IaaS)
Cloud service model that provisions virtual machines and network infrastructure.
Injector
A device that can supply Power over Ethernet (PoE) if the Ethernet switch ports do not support it.
Inkjet Printer
Type of printer where colored ink is sprayed onto the paper using microscopic nozzles in the print head. There are two main types of ink dispersion system: thermal shock (heating the ink to form a bubble that bursts through the nozzles) and piezoelectric (using a tiny element that changes shape to act as a pump).
In-Plane Switching
Type of TFT display with the best overall quality, including wide viewing angles, good contrast ratio, and good response times (on premium units).
Input Voltage
Range of alternating current (AC) voltages that a PSU can accept when connected to grid power. Some PSUs are manually switched between low-line 110–120 VAC and high-line 220–240 VAC.
Input / Output Operations Per Second (IOPS)
Performance indicator that measures the time taken to complete read/write operations.
Insulation Displacement Connector (IDC)
Block used to terminate twisted pair cabling at a wall plate or patch panel available in different formats, such as 110, BIX, and Krone.
Integrated Drive Electronics (IDE)
Legacy mass storage bus, most commonly implemented as extended IDE (EIDE) and also referred to as parallel advanced technology attachment (PATA). Each IDE controller port supports two devices connected over ribbon cable with three connectors (controller, primary device, and secondary device).
Intel
Intel processors were used in the first IBM PCs, and the company’s CPUs and chipsets continue to dominate the PC and laptop market.
Internet Message Access Protocol (IMAP)
Application protocol providing a means for a client to access and manage email messages stored in a mailbox on a remote server. IMAP4 utilizes TCP port number 143, while the secure version IMAPS uses TCP/993.
Internet of Things (IoT)
Devices that can report state and configuration data and be remotely managed over IP networks.
Internet Protocol (IP)
Network (Internet) layer protocol in the TCP/IP suite providing packet addressing and routing for all higher-level protocols in the suite.
Internet Service Provider (ISP)
Provides Internet connectivity and web services to its customers.
Intrusion Detection System
Security appliance or software that analyzes data from a packet sniffer to identify traffic that violates policies or rules.
Inverter
Fluorescent lamp backlights require AC power. An inverter component converts DC power from the motherboard to AC. The inverter can fail separately to the backlight.
IPv4
Version of the Internet Protocol that uses 32-bit address values and subnet masks typically expressed in dotted decimal notation.
IPv6
Version of the Internet Protocol that uses 64-bit address values typically expressed in canonical hex notation with slash notation network prefixes.
Jitter
Variation in the time it takes for a signal to reach the recipient. Jitter manifests itself as an inconsistent rate of packet delivery. If packet loss or delay is excessive, then noticeable audio or video problems (artifacts) are experienced by users.
Land Grid Array (LGA)
CPU socket form factor used predominantly by Intel where connector pins are located on the socket.
Laser Printer
Type of printer that develops an image on a drum by using electrical charges to attract special toner, then applying it to paper. The toner is then fixed to the paper using a high-heat and pressure roller (fuser). The process can be used with black toner only or CMYK toner cartridges to create full-color prints.
Latency
Time taken for a signal to reach the recipient, measured in milliseconds. Latency is a particular problem for two-way applications, such as VoIP (telephone) and online conferencing.
Lease (DHCP)
Address configuration assigned by a DHCP server to a client for a limited period.
Legacy System
Hardware or software product that is no longer supported by its vendor and therefore no longer provided with security updates and patches.
Light Emitting Diode (LED)
Small, low-power lamps used both as diagnostic indicators, the backlight for a TFT display, and (as an organic LED array) in high-quality flat panels.
Lightning
Proprietary connector and interface used by Apple iPhone and iPad devices.
Lightweight Directory Access Protocol (LDAP)
Protocol used to access network directory databases, which store information about authorized users and their privileges, as well as other organizational information.
Liquid Cooling
Cooling system that uses system of pipes, water blocks, and pumps to transfer heat away from components.
Liquid Crystal Display (LCD)
Flat-panel display technology where the image is made up of liquid crystal cells with color filters controlled using electrical charges. The display must be illuminated by a backlight.
Load Balancer
Type of switch, router, or software that distributes client requests between different resources, such as communications links or similarly configured servers. This provides fault tolerance and improves throughput.
Local Area Network (LAN)
Network scope restricted to a single geographic location and owned/managed by a single organization.
Local Connector (LC)
Small form factor push-pull fiber optic connector; available in simplex and duplex versions.
Location Service
Feature of mobile computing that identifies or estimates the device’s geographical position using GPS and/or network data.
Long Term Evolution (LTE)
Packet data communications specification providing an upgrade path for both GSM and CDMA cellular networks. LTE Advanced is designed to provide 4G standard network access.
long-range fixed wireless
Ground-based microwave transmission that supports long distances over precisely aligned directional antennas. These products can either make privileged use of licensed frequency bands or use public unlicensed radio-frequency spectrum.
Loopback Adapter
Tool used to verify the integrity of a network interface port by checking that it can receive a signal generated by itself.
M.2
Hardware specification for internal adapter cards. M.2 is often used for PCIe-based SSDs.
Maintenance Kit
On a laser printer, the fuser unit (the part that fuses toner onto the paper) needs replacing according to the maintenance kit schedule. A maintenance kit also includes new pickup, feed, and separation rollers. It may also include transfer components (roller or belt), or these may be replaced on a different schedule, depending on the printer model.
Managed Switch
Ethernet switch that is configurable via a command-line interface or SDN controller.
Mass Storage
Device with a persistent storage mechanism, such as hard drives, solid state drives, and optical drives.
Media Access Control (MAC)
Hardware address that uniquely identifies each network interface at layer 2 (Data Link). A MAC address is 48 bits long with the first half representing the manufacturer’s organizationally unique identifier (OUI).
Memory Card
Solid state flash memory provisioned as a peripheral device in a proprietary adapter card form factors, such as Secure Digital and microSD.
Metered Utilization
Feature of cloud service models that allows customers to track and pay for precise compute, storage, and network resource units.
Metropolitan Area Network (MAN)
Network scope covers the area of a city (that is, no more than tens of kilometers).
Microsoft 365
Mobile/cloud computing office productivity and data storage suite operated by Microsoft.
Mobile Application Management (MAM)
Enterprise management function that enables control over apps and storage for mobile devices and other endpoints.
Mobile Device Management (MDM)
Process and supporting technologies for tracking, controlling, and securing the organization’s mobile infrastructure.
Modular Power Supply (PSU)
PSU design where power cables can be attached to ports on the unit as needed.
Moles Connector
Legacy power connector for internal devices such as hard drives and optical drives.
mSATA
Connector form factor for internal solid state drives.
Multicore
CPU design that puts two chips onto the same package. Most CPUs are multicore (more than two cores).
Multi mode Fiber (MMF)
Fiber optic cable type using LED or vertical cavity surface emitting laser optics and graded using optical multimode types for core size and bandwidth.
Multiple Input Multiple Output (MIMO)
Use of multiple reception and transmission antennas to boost wireless bandwidth via spatial multiplexing and to boost range and signal reliability via spatial diversity.
Multi socket
Motherboard configuration with multiple CPU sockets. The CPUs installed must be identical.
Multithreading
CPU architecture that exposes two or more logical processors to the OS, delivering performance benefits similar to multicore and multisocket to threaded applications.
Multiuser MIMO (MU-MIMO)
Use of spatial multiplexing to allow a wireless access point to support multiple client stations simultaneously.
MX Record
Type of DNS resource record used to identify the email servers used by a domain.
Near-Field Communication
Standard for two-way radio communications over very short (around four inches) distances, facilitating contactless payment and similar technologies. NFC is based on RFID.
NetBIOS
Session management protocol used to provide name registration and resolution services on legacy Microsoft networks.
Network Address Translation (NAT)
Routing mechanism that conceals internal addressing schemes from the public Internet by translating between a single public address on the external side of a router and private, non-routable addresses internally.
Network Attached Storage (NAS)
Storage device enclosure with network port and an embedded OS that supports typical network file access protocols (FTP and SMB for instance).
Network Interface Card (NIC)
Adapter card that provides one or more Ethernet ports for connecting hosts to a network so that they can exchange data over a link.
Network Mask
Number of bits applied to an IP address to mask the network ID portion from the host/interface ID portion.
Network Topology Diagram
Documentation showing how network nodes are connected by cabling or how they are logically identified and connected, such as in IP networks.
New Technology Filing System (NTFS)
64-bit default file system for Windows, with file-by-file compression and RAID support as well as advanced file attribute management tools, encryption, and disk quotas.
Non-compliant System
System whose configuration is different from its secure baseline.
NSlookup Command
Cross-platform command tool for querying DNS resource records.
NTFS Permissions
ACL that mediates local and network access to a file system object under Windows when the volume is formatted with NTFS.
Octal Notation
Linux file-permission mode that uses numeric values to represent permissions.
On Site vs. Off Site
Media rotation scheme that ensures at least one copy of data is held at a different location to mitigate the risk of a disaster that destroys all storage at a single site.
OneDrive
Cloud storage service operated by Microsoft and closely integrated with Windows.
On-path Attach
Attack where the threat actor makes an independent connection between two victims and is able to read and possibly modify traffic.
Open Source
Licensing model that grants permissive rights to end-users, such as to install, use, modify, and distribute a software product and its source code, as long as redistribution permits the same rights.
Operator
Programming object that can resolve the truth value of a condition, such as whether one variable is equal to another.
Organizational Unit (OU)
Structural feature of a network directory that can be used to group objects that should share a common configuration or organizing principle, such as accounts within the same business department.
Original Equipment Manufacturer (OEM)
In PC terms, companies that sell Windows co-branded under their own logo. OEM Windows licenses are valid only on the system that the software was installed on, and the OEM must provide support.
Palm Print Scanner
Biometric camera-based scanner that uses unique features of a palm shown by visible and infrared light.
Password Attack
Any attack where the attacker tries to gain unauthorized access to and use of passwords.
Password Manager
Software that can suggest and store site and app passwords to reduce risks from poor user choices and behavior. Most browsers have a built-in password manager.
Path Ping Command
Windows utility for measuring latency and packet loss across an internetwork.
Pattern Lock
Mobile-device authentication mechanism that requires the user to input a join-the-dots pattern to unlock the device.
Performance Monitor (perfuming.msc)
Console for reporting and recording resource utilization via counter data for object instances.
Personal Government Issued Information
Data related to identity documents issued by governments, such as passports, social security IDs, and driving licenses, that is liable to be subject to strict legal and regulatory compliance requirements.
Personal Identification Number (PIN)
Number used in conjunction with authentication devices such as smart cards; as the PIN should be known only to the user, loss of the smart card should not represent a security risk.
Personalization Settings
Windows Settings pages related to customizing the appearance of the desktop using themes.
Personally Identifiable Information (PII)
Data that can be used to identify or contact an individual (or in the case of identity theft, to impersonate him or her).
Phishing
Email-based social engineering attack, in which the attacker sends email from a supposedly reputable source, such as a bank, to try to elicit private information from the victim.
Phone Settings
Windows Settings pages for associating a smartphone with Windows.
Physical Destruction
Using drilling, shredding, incineration, or degaussing of storage media before recycling or repurposing to minimize the risk of leaving persistent data remnants.
Physical Placement
Considerations for installation location for PC and network devices to ensure reliable and secure operation.
Piggy Backing
Allowing a threat actor to enter a site or controlled location without authorization
PIN Code Lock
Basic mobile-device authentication mechanism that requires the correct number or passcode to unlock the device.
Ping Command
Cross-platform command tool for testing IP packet transmission.
PKG
macOS installer format that supports complex setup tasks.
Plug-in (browser)
Software installed to a web browser to handle multimedia objects embedded in web pages. Use of most plug-in types is now deprecated.
Pop-up Blocker
Browser feature or extension that prevents sites from creating new browser windows.
Port Forwarding
Process in which a router takes requests from the Internet for a particular application (such as HTTP) and sends them to a designated host on the LAN.
Port Mapping
port mapping Type of port forwarding where the external port is forwarded to a different internal port on the LAN host.
Port Triggering
Mechanism to configure access through a firewall for applications that require more than one port. Basically, when the firewall detects activity on outbound port A destined for a given external IP address, it opens inbound access for the external IP address on port B for a set period.
Power Failure
Complete loss of building power.
Power Options
Control Panel app related to configuring power button/lid events and power-saving modes.
Power Users
One of the default Windows group accounts. Its use is deprecated, but it is still included with Windows to support legacy applications.
PowerShell (PS)
Command shell and scripting language built on the .NET Framework that use cmdlets for Windows automation.
Pre-boot Execution Environment (PXE)
Feature of a network adapter that allows the computer to boot by contacting a suitably configured server over the network.
Pre-shared Key (PSK)
Wireless network authentication mode where a passphrase-based mechanism is used to allow group authentication to a wireless network. The passphrase is used to derive an encryption key.
Pretexting
Social engineering tactic where a team will communicate, whether directly or indirectly, a lie or half-truth in order to get someone to believe a falsehood.
Privacy Settings
Windows Settings pages related to personal data collection and use.
Private Browsing
Browser mode in which all session data and cache is discarded and tracking protection features are enabled by default.
Private Key
In asymmetric encryption, the private key is known only to the holder and is linked to, but not derivable from, a public key distributed to those with whom the holder wants to communicate securely. A private key can be used to encrypt data that can be decrypted by the linked public key or vice versa.
Process
Software program that has been executed and is running in system memory.
Programs and Features
Control Panel applet allowing management of Windows Features and third-party software.
Prohibited Content
Data found on a computer system that is not permitted by policy or that is not compliant with relevant legislation or regulations.
Protected Health Information (PHI)
Data that can be used to identify an individual and includes information about past, present, or future health as well as related payments and data used in the operation of a healthcare business.
Proxy Server
Server that mediates the communications between a client and another server. It can filter and often modify communications as well as provide caching services to improve performance.
PS Command
Linux command for retrieving process information.
PSI
Extension for the PowerShell script format.
Public Key
During asymmetric encryption, this key is freely distributed and can be used to perform the reverse encryption or decryption operation of the linked private key in the pair.
pwd Command
Linux command for showing the current directory (“Print Working Directory”).
PY
Extension for a script written in the Python programming language.
Python
High-level programming language that is widely used for automation.
Quarantine
The process of isolating a file, computer system, or computer network to prevent the spread of a virus or another cybersecurity incident.
Quick Assist
Windows support feature allowing remote screen-sharing over the Internet.
Ransomware
Malware that tries to extort money from the victim by blocking normal operation of a computer and/or encrypting the victim’s files and demanding payment.
Recovery
Operation to recover system functionality and/or data integrity using backup media.
Recovery Partition
OEM recovery media enabling the user to reset the system to its factory configuration.
Recycle Bin
When files are deleted from a local hard disk, they are stored in the Recycle Bin. They can be recovered from here if so desired.
Redirection
Consequence of malware infection where DNS and/or search results are corrupted to redirect requests from legitimate site hosts to spoofed sites or ads.
Registry Editor (regedit)
Tool for making direct edits to the registry database, such as adding or modifying keys or values. The Registry Editor can be used to make backups of the registry.
Regulated Data
Information that has storage and handling compliance requirements defined by national and state legislation and/or industry regulations.
Remote Access Trojan (RAT)
Malware that creates a backdoor remote administration channel to allow a threat actor to access and control the infected host.
Remote Assistance (msra.exe)
Windows remote-support feature allowing a user to invite a technical support professional to provide assistance over a network using chat. The user can also grant the support professional control over his or her desktop. Remote Assistance uses the same RDP protocol as Remote Desktop.
Remote Authentication Dial-in User Service (RADIUS)
AAA protocol used to manage remote and wireless authentication infrastructures.
Remote Desktop Protocol (RDP)
Application protocol for operating remote connections to a host using a graphical interface. The protocol sends screen data from the remote host to the client and transfers mouse and keyboard input from the client to the remote host. It uses TCP port 3389.
Remote Disc
macOS tool for sharing an optical drive over the network.
Remote Monitoring and Management (RMM)
Category of support software designed for outsourced management of client networks by MSPs.
Remote Wipe
Software that allows deletion of data and settings on a mobile device to be initiated from a remote server.
Reservation (DHCP)
DHCP configuration that assigns either a prereserved or persistent IP address to a given host, based on its hardware address or other ID.
Reset this PC
Windows feature to attempt system recovery by reinstalling Windows from source
Resource Monitor (resmon.exe)
Console for live monitoring of resource utilization data for the CPU and GPU, system memory, disk/file system, and network.
Retina Scanner
Biometric scanner based on analysis of the unique pattern of blood vessels at the back of the eye.
Risk
Likelihood and impact (or consequences) of a threat actor exercising a vulnerability.
Risk Analysis
Process for qualifying or quantifying the likelihood and impact of a factor.
rm Command
Command-line tool for deleting file system objects in Linux.
rmdir command
Command-line tool for deleting directories in Windows. The /s switch enables the deletion of non-empty directories.
Roaming Profile
Configuring a network share to hold user profile data. The data is copied to and from the share at logon and logoff.
robocopy Command
Command-line file copy utility recommended for use over the older xcopy.
Roll Back Updates/Drivers
Windows troubleshooting feature that allows removal of an update or reversion to a previous driver version.
Root Access (mobile)
Gaining superuser-level access over an Android-based mobile device.
Rootkit
Class of malware that modifies system files, often at the kernel level, to conceal its presence.
Run as Administrator
Windows feature that requires a task to be explicitly launched with elevated privileges and consented to via UAC.
Run Dialog
Windows interface for executing commands.
Safe Mode
Troubleshooting startup mode that loads a limited selection of drivers and services.
Samba
Linux software package that implements Server Message Block (SMB) file/print sharing, primarily to support integration with Windows hosts.
Retention
Process an organization uses to maintain the existence of and control over certain data in order to comply with business policies and/or applicable laws and regulations.
Rogue Antivirus
Spoofed desktop notifications and browser ads designed to alarm users and promote installation of Trojan malware.
Sandbox
Computing environment that is isolated from a host system to guarantee that the environment runs in a controlled, secure fashion. Communication links between the sandbox and the host are usually completely prohibited so that malware or faulty software can be analyzed in isolation and without risk to the host.
Sanitization
Process of thoroughly and completely removing data from a storage medium so that file remnants cannot be recovered.
Screen Lock
Mobile-device mechanism that locks the screen after a period of inactivity.
Screened Subnet
Segment isolated from the rest of a private network by one or more firewalls that accepts connections from the Internet over designated ports.
Screensaver Lock
Security mechanism that locks the desktop after a period of inactivity and requires the user to authenticate to resume.
Screen-Sharing
Software that allows clients to view and control the desktop over a network or the Internet.
Script
Series of simple or complex commands, parameters, variables, and other components stored in a text file and processed by a shell interpreter.
Secure Connection
Using HTTPS to browse a site where the host has presented a valid digital certificate issued by a CA that is trusted by the browser. A padlock icon is shown to indicate the secure status of the connection.
Secure Erase (SE)
Method of sanitizing a drive using the ATA command set.
Secure Shell (SSH)
Application protocol supporting secure tunneling and remote terminal emulation and file copy. SSH runs over TCP port 22.
Security Group
Access control feature that allows permissions to be allocated to multiple users more efficiently.
Service Set Identifier (SSID)
Character string that identifies a particular wireless LAN (WLAN).
Services Console (services.msc)
Windows machines run services to provide functions; for example, Plug-and-Play, the print spooler, DHCP client, and so on. These services can be viewed, configured, and started/stopped via the Services console. You can also configure which services run at startup using msconfig. You can view background services (as well as applications) using the Processes tab in Task Manager.
sfc Command
Command-line utility that checks the integrity of system and device driver files.
SH
Extension for a Linux shell script file format. The shebang in the first line of the script identifies the shell type (Bash, for instance).
Shell
System component providing a command interpreter by which the user can use a kernel interface and operate the OS.
Short Message Service (SMS)
System for sending text messages between cell phones.
Shoulder Surfing
Social engineering tactic to obtain someone’s password or PIN by observing him or her as he or she types it in.
Shutdown Command
Command-line tool for shutting down or restarting the computer. The command is supported by Windows and Linux, though with different syntax.
Simultaneous Authentication of Equals (SAE)
Personal authentication mechanism for Wi-Fi networks introduced with WPA3 to address vulnerabilities in the WPA-PSK method.
Single Sign On (SSO)
Authentication technology that enables a user to authenticate once and receive authorizations for multiple services.
Sleep
Power-saving mode in Windows. On a laptop, this functions much like standby, but on a desktop, the system also creates a hibernation file before entering the standby state.
Smart Card
Security device similar to a credit card that can store authentication information, such as a user’s private key, on an embedded cryptoprocessor.
Social Engineering
Activity where the goal is to use deception and trickery to convince unsuspecting users to provide sensitive data or to violate security guidelines.
Soft Token
Either an additional code to use for 2-step verification, such as a one-time password, or authorization data that can be presented as evidence of authentication in an SSO system.
Sound Applet
Control Panel applet related to speaker and microphone configuration plus Windows sound events and notifications.
Spear Phishing
Email-based or web-based form of phishing that targets specific individuals.
Spinning Wait Cursor
macOS indicator that a process is busy and is not able to accept input.
Splash Screen
Displaying terms of use or other restrictions before use of a computer or app is allowed.
Spoofing
Attack technique where the threat actor disguises his or her identity or impersonates another user or resource.
Spotlight Search
macOS file system search tool.
Spyware
Software that records information about a PC and its users, often installed without the user’s consent.
Standard Account
Non-privileged user account in Windows that typically has membership of the Users security group only.
Standard Formatting
Using a vendor tool to delete the file system and/or partition table on storage media before recycling or repurposing. This method carries the greatest risk of leaving persistent data remnants.
Standard Operating Procedure (SOP)
Documentation of best practice and work instructions to use to perform a common administrative task.
Standby
Power-saving mode where power to all compatible components except system memory is cut. Note that systems on standby still consume some electricity.
Startup
Apps and scripts set to run when the computer starts or when the user signs in. Startup items can be configured as shortcuts, registry entries, or Task Scheduler triggers.
Startup Repair
Troubleshooting boot options that allow use of tools such as safe mode and recovery discs.
Storage Spaces
Windows feature for creating a single storage resource from multiple devices. Data can be protected against device failure by RAID-like mirroring or parity.
Structured Query Language injection (SQL injection)
Attack that injects a database query into the input data directed at a server by accessing the client side of the application.
su/sudo Commands
Linux commands allowing a user to use the root account or execute commands restricted to privileged users.
Surge Suppressor
A simple device intended to protect electrical devices against the damaging effects of a power spike.
Swipe
Mobile gesture that unlocks the screen without requiring authentication.
Symbolic Mode
Syntax for setting Linux permissions that uses characters to represent permissions values.
Symmetric Encryption
Two-way encryption scheme in which encryption and decryption are both performed by the same key. Also known as shared-key encryption.
Synthetic Full Backup
Job type that combines incremental backup jobs to synthesize a full backup job. Synthetic full backups have the advantage of being easy to restore from while also being easy on bandwidth across the network as only changes are transmitted.
System Applet
Control Panel applet relating to basic system settings, such as host name and network type, System Protection, performance settings, and virtual memory.
System Configuration Utility (msconfig.exe)
Utility for configuring Windows startup settings.
System Information (msinfo32.exe)
Utility for configuring Windows startup settings.
System Preferences
macOS control panel hosting multiple prefpane configuration utilities.
System Requirements
Minimum specifications for CPU speed, memory, and disk capacity for installing an OS or app.
System Restore (rstrui.exe)
Windows System Protection feature that allows the configuration to be reverted to a restore point.
System Settings
Windows Settings pages relating to basic and advanced system settings.
Tailgating
Social engineering technique to gain access to a building by following someone who is unaware of their presence.
Task Manager (taskmgr.exe)
Windows utility used to monitor and manage process execution, resource utilization, user sessions, startup settings, and service configuration.
Task Scheduler
Enables execution of an action (such as running a program or a script) automatically at a pre-set time or in response to some sort of trigger.
Temporal Key Integrity Protocol (TKIP)
Mechanism used in the first version of WPA to improve the security of wireless encryption mechanisms, compared to the flawed WEP standard.
Terminal
Software that implements input and output for a command shell.
Terminal Access Controller Access Control System Plus (TACACS+)
AAA protocol developed by Cisco that is often used to authenticate to administrator accounts for network appliance management.
This PC
File system object representing a Windows computer and the disk drives installed to it.
Threat
Potential for an entity to exercise a vulnerability (that is, to breach security).
Threat Actor
Person or entity responsible for an event that has been identified as a security incident or as a risk.
Ticketing System
Database software designed to implement a structured support process by identifying each case with a unique job ticket ID and with descriptive fields to record how the issue was resolved.
Time & Language Settings
Windows Settings pages allowing configuration of default data formats (date, currency, and so on), location information, and keyboard input locale.
Time Drift
Situation where hosts on a network are not closely synchronized to the same date/time source.
Time Machine
App facilitating backup operations in macOS.
top Command
Interactive Linux command for monitoring process information.
traceroute/tracert Command
Diagnostic utilities that trace the route taken by a packet as it “hops” to the destination host on a remote network. tracert is the Windows implementation, while traceroute runs on Linux.
Trojan
Malicious software program hidden within an innocuous-seeming piece of software. Usually, the Trojan is used to try to compromise the security of the target computer.
Trusted Platform Module (TPM)
Specification for secure hardware-based storage of encryption keys, hashed passwords, and other user- and platform-identification information.
Trusted Source
Installer package that can be verified by a digital signature or cryptographic hash.
Unattended Installation
Deployment method where installation choices are saved in an answer file or script so that the setup program executes without manual intervention.
Under-Voltage Event
When the power that is supplied by the electrical wall socket is insufficient to allow the computer to function correctly. Under-voltage events are long sags in power output that are often caused by overloaded or faulty grid distribution circuits or by a failure in the supply route from electrical power station to a building.
Unified Endpoint Management (UEM)
Enterprise software for controlling device settings, apps, and corporate data storage on all types of fixed, mobile, and IoT computing devices.
Uninterruptible Power Supply (UPS)
Battery-powered device that supplies AC power that an electronic device can use in the event of power failure.
Universal Plug-and-Play (UPnP)
Protocol framework allowing network devices to autoconfigure services, such as allowing a games console to request appropriate settings from a firewall.
UNIX Systems
UNIX is a family of more than 20 related operating systems that are produced by various companies. It can run on a wide variety of platforms. UNIX offers a multitude of file systems in addition to its native system. UNIX remains widely deployed in enterprise data centers to run mission-critical applications and infrastructure.
Unprotected System
System where one or more required security controls (antivirus or firewall, for example) are missing or misconfigured.
Untrusted Source
Installer package whose authenticity and integrity cannot be verified.
Update & Security settings
Windows Settings pages related to configuring automatic patching, deploying feature updates, and managing security features.
Update Limitation
Product life cycle and procurement consideration where a device or product no longer receives a full range of updates or support from its vendor.
Upgrade Path
Earlier versions of an OS that support an in-place upgrade to a newer version, retaining settings, third-party apps, and user data files.
User Account Control (UAC)
Windows feature designed to mitigate abuse of administrative accounts by requiring explicit consent to use privileges.
User Accounts Applet
Control Panel app relating to user account creation and maintenance.
Variable
Identifier for a value that can change during program execution. Variables are usually declared with a particular data type.
VBS
Extension for the Visual Basic Script file format.
Video Conferencing
Software that allows users to configure virtual meeting rooms, with options for voice, video, instant messaging, and screen-sharing.
Video Surveillance
Software that allows users to configure virtual meeting rooms, with options for voice, video, instant messaging, and screen-sharing.
VIM
Command-line text editor that extends the original vi software. Vim uses a command mode for file operations and an insert mode for editing.
Virtual Network Computing (VNC)
Remote access tool and protocol. VNC is the basis of macOS screen-sharing.
Virtual Private Network (VPN)
Secure tunnel created between two endpoints connected via an unsecure transport network (typically the Internet).
Virus
Malicious code inserted into an executable file image. The malicious code is executed when the file is run and can deliver a payload, such as attempting to infect other files.
Vishing
Social engineering attack where the threat actor extracts information while speaking over the phone or leveraging IP-based voice messaging services (VoIP).
Visual Basic Script (VBScript)
A command shell and scripting language built on the .NET Framework, which allows the administrator to automate and manage computing tasks.
Vulnerability
Weakness that could be triggered accidentally or exploited intentionally to cause a security breach.
Whaling
An email-based or web-based form of phishing that targets senior executives or wealthy individuals.
WI-FI Protected Access (WPA)
Standards for authenticating and encrypting access to Wi-Fi networks.
Windows
Windows started as version 3.1 for 16-bit computers. A workgroup version provided rudimentary network facilities. Windows NT 4 workstations and servers (introduced in 1993) provided reliable 32-bit operation and secure network facilities, based around domains. The Windows 9x clients (Windows 95, 98, and Me) had far-lower reliability and support only for workgroups but were still hugely popular as home and business machines. Windows 2000 and Windows XP workstations married the hardware flexibility and user interface of Windows 9x to the reliability and security of Windows NT, while the server versions saw the introduction of Active Directory for managing network objects. The subsequent client releases of Windows (Vista/7/8/8.1) feature a substantially different interface (Aero) with 3-D features as well as security improvements. The latest client versions—Windows 10 and Windows 11—are designed for use with touch-screen devices.
Windows Defender Antivirus
Security scanner installed and enabled by default in Windows that provides protection against general malware types.
Windows Defender Firewall
Built-in, host-based filtering of network connections.
Windows Edition
Feature restrictions applied to Windows to distinguish different markets, pricing, and licensing models, such as home versus professional versus enterprise.
Windows Hello
Feature that supports passwordless sign-in for Windows.
Windows Recovery Environment (WinRE)
Windows troubleshooting feature that installs a command shell environment to a recovery partition to remediate boot issues.
Windows Security
Touch-enabled app for configuring features such as firewall and antivirus.
Windows Settings
Touch-enabled interface for managing user and system settings in Windows.
winver Command
Command-line tool for reporting Windows version information.
WinX menu
Start button shortcut menu with quick access to principal configuration and management utilities.
Wireless Wide Area Network (WWAN)
Network covering a large area using wireless technologies, such as a cellular radio data network or line-of-sight microwave transmission.
Workgroup
Group of network hosts that shares resources in a peer-to-peer fashion. No one computer provides a centralized directory.
Worm
Type of malware that replicates between processes in system memory and can spread over client/server network connections.
xcopy Command
Command-line directory and file copy utility offering improved functionality compared to the basic copy command.
Yum
Package manager for installing, maintaining, inventorying, and removing software from the Red Hat family of Linux distributions.
Zero-Day
Vulnerability in software that is unpatched by the developer or an attack that exploits such a vulnerability.
