Complete CompTIA Acronym List

Every acronym across CompTIA Security+, Network+, and A+ in one place, grouped by domain. The complete reference — skim it here, then drill by certification.

361 acronyms|21 domains

Drill these interactively

Application Security (16)

APIApplication Programming Interface: Set of protocols and tools enabling software applications to communicate with each other.
ASLRAddress Space Layout Randomization: OS security technique that randomizes memory addresses used by processes to prevent buffer overflow exploits.
CAPTCHACompletely Automated Public Turing test to tell Computers and Humans Apart: Challenge-response test used to determine whether a user is human, preventing automated bot abuse.
CMSContent Management System: Software platform for creating and managing digital content, often web-based.
CSRFCross-Site Request Forgery: Web attack that forces an authenticated user to submit unintended requests to a trusted application.
DEPData Execution Prevention: Hardware/OS security feature preventing code execution from memory regions marked as non-executable.
DLLDynamic Link Library: Shared library file in Windows containing code and data that can be loaded by multiple programs simultaneously.
ERPEnterprise Resource Planning: Integrated software system managing core business processes like finance, HR, and supply chain.
HTMLHypertext Markup Language: Standard markup language for creating and structuring content on web pages.
JSONJavaScript Object Notation: Lightweight data interchange format that is human-readable and easy for machines to parse and generate.
OWASPOpen Web Application Security Project: Nonprofit organization producing tools, guides, and the Top 10 list for web application security.
SQLStructured Query Language: Standard language for managing and querying relational databases; SQL injection is a top web vulnerability.
URIUniform Resource Identifier: String identifying a resource by name, location, or both, encompassing both URLs and URNs.
URLUniform Resource Locator: Web address specifying the protocol, host, and path to locate a resource on the internet.
XMLExtensible Markup Language: Markup language defining rules for encoding documents in a human-readable and machine-readable format.
XSSCross-Site Scripting: Web vulnerability where attackers inject malicious scripts into trusted websites viewed by other users.

Cryptography (41)

AESAdvanced Encryption Standard: Symmetric block cipher using 128, 192, or 256-bit keys; the current standard for encrypting data at rest and in transit.
AHAuthentication Header: IPSec protocol providing data integrity and origin authentication but not encryption.
CACertificate Authority: Trusted entity that issues, manages, and revokes digital certificates within a PKI hierarchy.
CCMPCounter Mode with Cipher Block Chaining Message Authentication Code Protocol: AES-based encryption protocol used in WPA2 to provide confidentiality, integrity, and authentication for wireless frames.
CRLCertificate Revocation List: Published list of serial numbers for certificates that a CA has revoked before their expiration date.
CSRCertificate Signing Request: Encoded message sent to a CA containing the public key and identity information to request a digital certificate.
DESData Encryption Standard: Legacy symmetric cipher using a 56-bit key, now considered insecure and replaced by AES.
DHEDiffie-Hellman Ephemeral: Key exchange variant that generates a new key pair per session, providing perfect forward secrecy.
DSADigital Signature Algorithm: Federal standard for digital signatures providing authentication and non-repudiation.
ECCElliptic Curve Cryptography: Public-key cryptography based on elliptic curve mathematics, providing strong security with smaller key sizes.
ESPEncapsulating Security Payload: IPSec protocol providing confidentiality, data integrity, and authentication for IP packets.
GCMGalois/Counter Mode: Authenticated encryption mode providing both confidentiality and data integrity at high speed.
GPGGNU Privacy Guard: Open-source implementation of the OpenPGP standard for encrypting and signing data and communications.
HMACHash-based Message Authentication Code: Mechanism combining a cryptographic hash with a secret key to verify both integrity and authenticity of a message.
HSMHardware Security Module: Tamper-resistant hardware device that manages, generates, and stores cryptographic keys securely.
IKEInternet Key Exchange: Protocol used to negotiate and establish security associations and keys for IPSec VPN tunnels.
IPSecInternet Protocol Security: Suite of protocols that authenticates and encrypts IP packets, commonly used for VPN tunnels.
IVInitialization Vector: Random or pseudo-random value prepended to plaintext before encryption to ensure unique ciphertext output.
KEKKey Encryption Key: Cryptographic key used to protect other keys during transport or storage.
OCSPOnline Certificate Status Protocol: Protocol for real-time checking of a digital certificate's revocation status against the CA.
PBKDF2Password-Based Key Derivation Function 2: Key derivation function applying a pseudorandom function with many iterations to slow brute-force attacks.
PEMPrivacy Enhanced Mail: Base64-encoded file format for storing certificates and cryptographic keys, recognizable by BEGIN/END headers.
PFSPerfect Forward Secrecy: Cryptographic property ensuring session keys are not compromised if the long-term private key is leaked.
PGPPretty Good Privacy: Encryption program providing cryptographic privacy and authentication for email and file encryption.
PKIPublic Key Infrastructure: Framework of roles, policies, and technology for creating, managing, and revoking digital certificates.
PSKPre-Shared Key: Shared secret distributed in advance between parties for authenticating a connection, commonly used in Wi-Fi and VPNs.
RARegistration Authority: Entity in a PKI that verifies certificate applicant identities before the CA issues a certificate.
RACEResearch and Development in Advanced Communications Technologies in Europe: European R&D program in advanced communications that contributed to the RIPEMD hash function family.
RSARivest, Shamir, Adleman: Asymmetric encryption algorithm based on the difficulty of factoring large prime numbers, widely used for digital signatures and key exchange.
SANSubject Alternative Name: X.509 certificate extension listing additional hostnames or IPs that the certificate is valid for.
SCEPSimple Certificate Enrollment Protocol: Protocol for simplified certificate issuance and management, commonly used for device enrollment.
SHASecure Hash Algorithm: Family of cryptographic hash functions (SHA-1, SHA-256, SHA-3) producing fixed-size digests for integrity verification.
SSLSecure Sockets Layer: Deprecated cryptographic protocol for securing communications; superseded by TLS.
TKIPTemporal Key Integrity Protocol: Encryption protocol used in WPA that wraps WEP with per-packet key mixing; now deprecated in favor of CCMP.
TLSTransport Layer Security: Cryptographic protocol providing encrypted, authenticated communication channels; successor to SSL.
WEPWired Equivalent Privacy: Obsolete wireless encryption standard with severe cryptographic weaknesses; should never be used.
WPAWi-Fi Protected Access: Wireless security protocol using TKIP encryption, an interim improvement over WEP before WPA2.
WPA2Wi-Fi Protected Access 2: Wireless security standard using AES-CCMP encryption, mandatory for Wi-Fi certification since 2006.
WPA3Wi-Fi Protected Access 3: Latest wireless security standard with SAE handshake, 192-bit enterprise mode, and forward secrecy.
WTLSWireless Transport Layer Security: Security protocol designed for wireless networks, based on TLS but optimized for low-bandwidth environments.
X.509X.509 Certificate Standard: ITU-T standard defining the format of public key certificates used in TLS, email signing, and code signing.

Data Protection (4)

EFSEncrypting File System: Windows feature that provides file-level encryption on NTFS volumes using certificate-based keys.
FDEFull Disk Encryption: Encryption of an entire storage device so all data is protected at rest, including the OS and temp files.
GFSGrandfather-Father-Son: Backup rotation scheme using daily, weekly, and monthly backups for efficient media reuse and data retention.
RAIDRedundant Array of Independent Disks: Storage technology combining multiple drives for redundancy, performance, or both using levels like 0, 1, 5, 6, and 10.

General Security Concepts (1)

CIAConfidentiality, Integrity, and Availability: The three core principles of information security that guide security policy and controls.

Hardware (35)

ACPIAdvanced Configuration and Power Interface: Open standard for OS-controlled hardware discovery, configuration, and power management.
AGPAccelerated Graphics Port: Legacy high-speed point-to-point bus for connecting video cards, replaced by PCIe.
AHCIAdvanced Host Controller Interface: Interface standard enabling advanced features like hot-swap and native command queuing for SATA devices.
BIOSBasic Input/Output System: Legacy firmware interface that initializes hardware during boot and provides runtime services for the OS.
CMOSComplementary Metal-Oxide Semiconductor: Chip that stores BIOS/UEFI settings such as date, time, and boot order, powered by a small battery.
CPUCentral Processing Unit: The primary processor that executes instructions and performs calculations in a computer system.
DDRDouble Data Rate: Memory technology that transfers data on both rising and falling clock edges, doubling throughput.
DIMMDual In-line Memory Module: Standard form factor for desktop RAM, using a 64-bit data path with pins on both sides.
DisplayPortDisplayPort: Digital display interface supporting high-resolution video, audio, and daisy-chaining of multiple monitors.
DVIDigital Visual Interface: Video display interface supporting both digital and analog signals for connecting monitors.
ESDElectrostatic Discharge: Sudden flow of static electricity between objects that can damage sensitive electronic components.
GPTGUID Partition Table: Modern disk partitioning scheme supporting drives over 2 TB and up to 128 partitions, paired with UEFI.
GPUGraphics Processing Unit: Specialized processor designed to accelerate rendering of images, video, and graphical computations.
HDDHard Disk Drive: Magnetic storage device using spinning platters and read/write heads for persistent data storage.
HDMIHigh-Definition Multimedia Interface: Audio/video interface for transmitting uncompressed digital data to displays and audio devices.
IDEIntegrated Drive Electronics: Legacy parallel interface standard for connecting hard drives and optical drives to a motherboard.
KVMKeyboard, Video, Mouse: Switch allowing a single keyboard, monitor, and mouse to control multiple computers.
LCDLiquid Crystal Display: Flat-panel display technology using liquid crystals modulated by electric current to produce images.
LEDLight-Emitting Diode: Semiconductor device that emits light when current passes through it, used in displays and indicators.
M.2M.2 Form Factor: Compact expansion card form factor for SSDs and wireless cards, supporting NVMe and SATA interfaces.
MBRMaster Boot Record: Legacy disk partitioning scheme limited to 4 primary partitions and 2 TB maximum drive size.
NICNetwork Interface Card: Hardware component that connects a computer to a network using wired or wireless connectivity.
NVMeNon-Volatile Memory Express: High-speed storage protocol designed for flash-based SSDs, communicating directly over PCIe bus.
OLEDOrganic Light-Emitting Diode: Display technology where organic compounds emit light, producing deep blacks and high contrast ratios.
PCIePeripheral Component Interconnect Express: High-speed serial bus standard for connecting expansion cards like GPUs, SSDs, and network cards.
POSTPower-On Self-Test: Diagnostic sequence run by BIOS/UEFI firmware at startup to verify hardware components are functional.
PSUPower Supply Unit: Component that converts AC power from the wall outlet to DC power for a computer's internal components.
RAMRandom Access Memory: Volatile system memory providing fast read/write access for actively running programs and data.
SATASerial Advanced Technology Attachment: Interface standard for connecting storage drives like HDDs and SSDs to a motherboard.
SO-DIMMSmall Outline Dual In-line Memory Module: Compact RAM module used in laptops and small form-factor systems, roughly half the size of a full DIMM.
SSDSolid-State Drive: Storage device using flash memory with no moving parts, offering faster access and greater durability than HDDs.
ThunderboltThunderbolt: High-speed interface combining PCIe and DisplayPort, supporting up to 40 Gbps (Thunderbolt 3/4) via USB-C.
UEFIUnified Extensible Firmware Interface: Modern firmware interface replacing BIOS, supporting Secure Boot, larger disks, and faster initialization.
USBUniversal Serial Bus: Standard interface for connecting peripherals, providing data transfer and power delivery.
VGAVideo Graphics Array: Legacy analog video interface standard using a 15-pin D-sub connector for display output.

Identity and Access Management (29)

AAAAuthentication, Authorization, and Accounting: Security framework that controls who can access resources, what they can do, and tracks their activity.
ABACAttribute-Based Access Control: Access control model evaluating attributes (user, resource, environment) to make authorization decisions.
ADActive Directory: Microsoft directory service for managing users, computers, and resources in a Windows domain environment.
CHAPChallenge Handshake Authentication Protocol: Authentication protocol using a three-way handshake with a shared secret, periodically re-verifying identity.
DACDiscretionary Access Control: Access control model where the resource owner determines who can access the resource.
EAPExtensible Authentication Protocol: Framework providing multiple authentication methods for wireless and point-to-point connections.
FACLFile System Access Control List: OS-level list specifying permissions granted to users and groups for file system objects.
GPOGroup Policy Object: Active Directory mechanism for centrally managing and configuring settings for users and computers in a domain.
HOTPHMAC-based One-Time Password: OTP algorithm generating passwords based on a counter value and shared secret.
IAMIdentity and Access Management: Framework of policies and technologies ensuring the right individuals access the right resources at the right time.
KDCKey Distribution Center: Central component in Kerberos that issues tickets for authenticated access to network services.
LDAPLightweight Directory Access Protocol: Protocol for accessing and managing distributed directory services over TCP port 389.
LDAPSLightweight Directory Access Protocol Secure: LDAP encrypted with TLS over port 636, securing directory queries and authentication.
MACMandatory Access Control: Access control model where the OS enforces access based on classification labels assigned to subjects and objects.
MFAMulti-Factor Authentication: Authentication requiring two or more verification factors from different categories: something you know, have, or are.
NTLMNT LAN Manager: Legacy Windows authentication protocol using challenge-response; considered less secure than Kerberos.
OAUTHOpen Authorization: Open standard for token-based authorization allowing third-party services limited access without sharing credentials.
OIDCOpenID Connect: Identity layer on top of OAuth 2.0 that provides authentication and user identity verification.
PAMPrivileged Access Management: Security framework for controlling, monitoring, and auditing all privileged access to critical resources.
PAPPassword Authentication Protocol: Simple authentication protocol transmitting credentials in cleartext; insecure and largely deprecated.
PEAPProtected Extensible Authentication Protocol: EAP variant that creates an encrypted TLS tunnel for secure authentication, commonly used in enterprise Wi-Fi.
RADIUSRemote Authentication Dial-In User Service: AAA protocol providing centralized authentication, authorization, and accounting for network access.
RBACRole-Based Access Control: Access control model assigning permissions to roles rather than individuals, simplifying administration.
SAMLSecurity Assertion Markup Language: XML-based framework for exchanging authentication and authorization data between an IdP and a service provider.
SCIMSystem for Cross-domain Identity Management: Open standard for automating the exchange of user identity information between identity domains.
SSOSingle Sign-On: Authentication scheme allowing users to log in once and access multiple applications without re-authenticating.
TACACS+Terminal Access Controller Access-Control System Plus: Cisco AAA protocol using TCP port 49, encrypting the full authentication session for network device administration.
TGTTicket-Granting Ticket: Kerberos credential obtained after initial authentication, used to request service tickets without re-entering credentials.
TOTPTime-based One-Time Password: OTP algorithm generating short-lived codes based on the current time and a shared secret.

IP Addressing (4)

APIPAAutomatic Private IP Addressing: Self-assigned IP address in the 169.254.x.x range when a DHCP server is unavailable.
CIDRClassless Inter-Domain Routing: IP addressing method using variable-length subnet masking to allocate addresses more efficiently than classful addressing.
EUIExtended Unique Identifier: 64-bit identifier used in IPv6 SLAAC to create the interface ID portion of an address from the MAC address.
VLSMVariable-Length Subnet Masking: Subnetting technique allowing different-sized subnets within the same network, optimizing IP address usage.

Mobile Devices (1)

APKAndroid Package Kit: File format used to distribute and install applications on the Android operating system.

Network Infrastructure (25)

BPDUBridge Protocol Data Unit: STP frame exchanged between switches to detect and prevent loops in bridged networks.
DWDMDense Wavelength Division Multiplexing: Fiber-optic technology transmitting multiple data streams simultaneously over different wavelengths of light.
FHRPFirst Hop Redundancy Protocol: Group of protocols (HSRP, VRRP, GLBP) providing default gateway redundancy through virtual IP sharing.
HSRPHot Standby Router Protocol: Cisco proprietary FHRP providing router failover by allowing two or more routers to share a virtual IP.
IDFIntermediate Distribution Frame: Wiring rack in a telecommunications room that connects to the MDF and distributes cabling to a floor or area.
iSCSIInternet Small Computer Systems Interface: Protocol carrying SCSI commands over IP networks, enabling block-level storage access over standard Ethernet.
LACPLink Aggregation Control Protocol: IEEE 802.3ad protocol that bundles multiple physical links into a single logical link for increased bandwidth and redundancy.
LLDPLink Layer Discovery Protocol: Vendor-neutral Layer 2 protocol used by devices to advertise their identity and capabilities on a LAN.
LWAPPLightweight Access Point Protocol: Protocol used by lightweight APs to communicate with and be managed by a wireless LAN controller.
MDFMain Distribution Frame: Primary wiring point in a building where external cabling connects to the internal network backbone.
MSTPMultiple Spanning Tree Protocol: IEEE 802.1s extension of RSTP supporting multiple spanning tree instances mapped to different VLANs.
NASNetwork-Attached Storage: Dedicated file storage device providing centralized file-level access to networked clients.
PoEPower over Ethernet: Technology delivering electrical power along with data over standard Ethernet cables to devices like APs and cameras.
RJ-45Registered Jack 45: Eight-pin connector used for Ethernet network cables, the standard for copper network terminations.
RSTPRapid Spanning Tree Protocol: IEEE 802.1w evolution of STP providing faster convergence when network topology changes.
SANStorage Area Network: High-speed dedicated network providing block-level access to consolidated storage for servers.
SDNSoftware-Defined Networking: Architecture separating the control plane from the data plane, enabling centralized and programmable network management.
SFPSmall Form-factor Pluggable: Compact hot-swappable transceiver module for fiber-optic and copper networking, supporting 1 Gbps.
SFP+Small Form-factor Pluggable Plus: Enhanced SFP transceiver supporting up to 10 Gbps for high-speed network connections.
SPANSwitched Port Analyzer: Switch feature that mirrors traffic from one or more ports to a monitoring port for network analysis.
STPSpanning Tree Protocol: Layer 2 protocol preventing broadcast loops in bridged networks by blocking redundant paths.
TCAMTernary Content-Addressable Memory: Specialized switch memory enabling high-speed lookups for ACLs, QoS, and routing decisions.
UTPUnshielded Twisted Pair: Common copper network cabling with twisted wire pairs and no additional shielding, used in Cat5e/Cat6 Ethernet.
VRRPVirtual Router Redundancy Protocol: Protocol providing automatic router failover by allowing multiple routers to share a virtual IP address.
VXLANVirtual Extensible LAN: Network virtualization technology encapsulating Layer 2 frames in UDP packets for scalable overlay networks.

Network Security (14)

ACLAccess Control List: A set of rules that filters network traffic or defines permissions for accessing system resources.
DKIMDomainKeys Identified Mail: Email authentication method using digital signatures to verify the sender domain and message integrity.
DMARCDomain-based Message Authentication, Reporting, and Conformance: Email authentication policy that builds on SPF and DKIM to prevent domain spoofing and phishing.
DMZDemilitarized Zone: Network segment between the internal network and the internet, hosting public-facing services while protecting internal resources.
DNSSECDomain Name System Security Extensions: Suite of extensions that adds cryptographic authentication to DNS responses to prevent spoofing.
NACNetwork Access Control: Security solution that enforces policy compliance on devices before granting network access.
NGFWNext-Generation Firewall: Advanced firewall combining traditional filtering with application awareness, IPS, and threat intelligence.
RASRemote Access Server: Server enabling remote users to connect to a network over dial-up or VPN connections.
SPFSender Policy Framework: Email authentication DNS record specifying which mail servers are authorized to send email for a domain.
SWGSecure Web Gateway: Security solution filtering unwanted software and malware from web traffic and enforcing internet policy.
UTMUnified Threat Management: All-in-one security appliance combining firewall, IDS/IPS, antivirus, content filtering, and VPN in a single device.
VLANVirtual Local Area Network: Logical network segmentation at Layer 2, isolating broadcast domains on a switch without separate physical networks.
VPNVirtual Private Network: Encrypted tunnel over a public network providing secure remote access or site-to-site connectivity.
WAFWeb Application Firewall: Security device filtering and monitoring HTTP traffic to protect web applications from attacks like XSS and SQL injection.

Network Services (15)

AAAAIPv6 Address Record: DNS record type mapping a hostname to a 128-bit IPv6 address.
CNAMECanonical Name Record: DNS record creating an alias that maps one domain name to another canonical domain name.
MXMail Exchange: DNS record specifying the mail server responsible for accepting email for a domain.
NSName Server Record: DNS record delegating a DNS zone to an authoritative name server.
PTRPointer Record: DNS record used for reverse DNS lookups, mapping an IP address to a hostname.
PXEPreboot Execution Environment: Standard for booting a computer from the network using DHCP and TFTP before loading a local OS.
QoSQuality of Service: Network mechanism that prioritizes certain traffic types to ensure performance for latency-sensitive applications like VoIP.
SIPSession Initiation Protocol: Signaling protocol for initiating, maintaining, and terminating VoIP and multimedia sessions.
SNTPSimple Network Time Protocol: Simplified version of NTP for time synchronization in environments where high accuracy is not required.
SOAStart of Authority: DNS record type containing authoritative information about a DNS zone, including the primary nameserver and serial number.
SRVService Record: DNS record specifying the hostname and port for a specific service, enabling service discovery.
TXTText Record: DNS record holding arbitrary text, commonly used for SPF, DKIM, and domain verification.
UPnPUniversal Plug and Play: Protocol suite enabling devices to discover each other and establish network services automatically, posing security risks.
VoIPVoice over Internet Protocol: Technology for delivering voice and multimedia over IP networks instead of traditional phone lines.
WINSWindows Internet Name Service: Legacy Microsoft service resolving NetBIOS names to IP addresses, largely replaced by DNS.

Network Troubleshooting (2)

OTDROptical Time-Domain Reflectometer: Fiber-optic testing instrument that measures signal loss, cable breaks, and splice quality by analyzing reflected light.
TDRTime-Domain Reflectometer: Copper cable testing instrument that identifies faults, breaks, and cable length by measuring signal reflections.

Networking (40)

APAccess Point: Network device that allows wireless clients to connect to a wired network.
ARPAddress Resolution Protocol: Layer 2 protocol that maps an IP address to a MAC address on a local network segment.
BGPBorder Gateway Protocol: Path-vector exterior gateway protocol used to exchange routing information between autonomous systems on the internet.
DHCPDynamic Host Configuration Protocol: Protocol that automatically assigns IP addresses and network configuration to devices on a network.
DNSDomain Name System: Hierarchical naming system that translates human-readable domain names to IP addresses.
FTPFile Transfer Protocol: Protocol for transferring files over TCP using port 21 for control and port 20 for data, transmitting in cleartext.
FTPSFile Transfer Protocol Secure: FTP with added TLS/SSL encryption for secure file transfers.
GREGeneric Routing Encapsulation: Tunneling protocol that encapsulates various network layer protocols inside point-to-point connections.
HTTPHypertext Transfer Protocol: Application layer protocol for transmitting web content over TCP port 80, without encryption.
HTTPSHypertext Transfer Protocol Secure: HTTP encrypted with TLS over TCP port 443, providing confidentiality and integrity for web traffic.
ICMPInternet Control Message Protocol: Network protocol used for diagnostic and error-reporting purposes, including ping and traceroute.
IGMPInternet Group Management Protocol: Protocol used by hosts and routers to manage multicast group membership on IPv4 networks.
IMAPInternet Message Access Protocol: Email retrieval protocol on port 143 that syncs messages on the server, allowing multi-device access.
IPInternet Protocol: Layer 3 protocol responsible for addressing and routing packets between hosts across networks.
ISPInternet Service Provider: Organization providing internet access and related services to customers.
L2TPLayer 2 Tunneling Protocol: VPN tunneling protocol that encapsulates PPP frames; typically paired with IPSec for encryption.
MACMedia Access Control: Unique 48-bit hardware address assigned to a NIC, used for communication on a local network segment.
MPLSMultiprotocol Label Switching: High-performance routing technique that directs data using labels rather than complex routing lookups.
NATNetwork Address Translation: Technique that maps private IP addresses to a public IP address for internet communication.
NetBIOSNetwork Basic Input/Output System: Legacy API for communication between applications on a LAN, used for name resolution and session management.
NTPNetwork Time Protocol: Protocol synchronizing clocks across network devices using UDP port 123, critical for log correlation.
PATPort Address Translation: NAT variant that maps multiple private IP addresses to a single public IP using different port numbers.
POP3Post Office Protocol v3: Email retrieval protocol on port 110 that downloads messages and typically removes them from the server.
PPPoEPoint-to-Point Protocol over Ethernet: Protocol encapsulating PPP frames inside Ethernet frames, commonly used by DSL providers for authentication.
RDPRemote Desktop Protocol: Microsoft protocol on port 3389 providing graphical remote access to Windows systems.
SCPSecure Copy Protocol: File transfer protocol using SSH encryption to securely copy files between hosts.
SFTPSSH File Transfer Protocol: Secure file transfer protocol running over SSH, providing encryption and authentication on port 22.
SHTTPSecure Hypertext Transfer Protocol: Deprecated protocol for encrypting individual HTTP messages at the application layer.
SMBServer Message Block: Network file sharing protocol on port 445 used primarily in Windows environments for file, printer, and serial access.
SMTPSimple Mail Transfer Protocol: Protocol for sending email messages between servers on TCP port 25, with port 587 for submission.
SNMPSimple Network Management Protocol: Protocol for monitoring and managing network devices, using agents and a management station via UDP ports 161/162.
SRTPSecure Real-Time Transport Protocol: Protocol providing encryption and authentication for RTP streams, securing VoIP and video communications.
SSHSecure Shell: Encrypted protocol on port 22 providing secure remote command-line access and file transfer.
SSIDService Set Identifier: Human-readable name identifying a wireless network, broadcast by access points.
TCPTransmission Control Protocol: Connection-oriented Layer 4 protocol providing reliable, ordered delivery through three-way handshake and acknowledgments.
TFTPTrivial File Transfer Protocol: Simple UDP-based file transfer protocol on port 69 with no authentication, used for PXE boot and firmware updates.
TTLTime to Live: Value limiting the lifetime of data in a network; in IP it counts hops, in DNS it defines cache duration.
UDPUser Datagram Protocol: Connectionless Layer 4 protocol offering fast, low-overhead delivery without guaranteed ordering or reliability.
WAPWireless Access Point: Networking device that allows wireless devices to connect to a wired network using Wi-Fi.
WLANWireless Local Area Network: Local area network using wireless communication, typically based on IEEE 802.11 standards.

Networking Fundamentals (12)

CSMA/CACarrier Sense Multiple Access with Collision Avoidance: Media access method used in wireless networks where devices listen before transmitting and use RTS/CTS to avoid collisions.
CSMA/CDCarrier Sense Multiple Access with Collision Detection: Media access method used in wired Ethernet where devices detect and retransmit after collisions.
IEEEInstitute of Electrical and Electronics Engineers: Professional organization that develops networking and technology standards like 802.11 and 802.1X.
LANLocal Area Network: Network connecting devices in a limited geographic area such as a building or campus.
LLCLogical Link Control: Upper sublayer of the data link layer that provides flow control and multiplexing for protocols.
MANMetropolitan Area Network: Network spanning a city or large campus, larger than a LAN but smaller than a WAN.
MTUMaximum Transmission Unit: Largest packet size that can be sent over a network link without fragmentation, typically 1500 bytes on Ethernet.
OUIOrganizationally Unique Identifier: First 24 bits of a MAC address identifying the hardware manufacturer, assigned by IEEE.
PDUProtocol Data Unit: Unit of data specified by a protocol at each OSI layer (frame, packet, segment, data).
PPPPoint-to-Point Protocol: Data link protocol for direct communication between two nodes, providing authentication and compression.
RFCRequest for Comments: Publication series by IETF documenting internet standards, protocols, and best practices.
WANWide Area Network: Network spanning a large geographic area, connecting multiple LANs across cities or countries.

Operating Systems (10)

BitLockerBitLocker Drive Encryption: Windows full-disk encryption feature using AES and typically the TPM chip for key protection.
BSODBlue Screen of Death: Windows stop error screen indicating a critical system error requiring restart.
exFATExtended File Allocation Table: File system optimized for flash media, removing FAT32's 4 GB file size limit while maintaining cross-platform support.
ext4Fourth Extended File System: Default Linux journaling file system supporting volumes up to 1 EiB and files up to 16 TiB.
FAT32File Allocation Table 32: Legacy file system with broad compatibility, limited to 4 GB maximum file size and 32 GB volumes in Windows.
MMCMicrosoft Management Console: Windows framework hosting administrative tools (snap-ins) for managing system components.
NTFSNew Technology File System: Windows file system supporting permissions, encryption, compression, and journaling.
OSOperating System: System software managing hardware resources and providing services for application programs.
RMMRemote Monitoring and Management: Software platform enabling IT administrators to monitor and manage endpoints remotely.
WMIWindows Management Instrumentation: Microsoft infrastructure for managing data and operations on Windows-based systems via scripting.

Physical Security (3)

HVACHeating, Ventilation, and Air Conditioning: Environmental control system critical for maintaining proper temperature and humidity in data centers.
RFIDRadio Frequency Identification: Technology using electromagnetic fields to identify and track tags attached to objects, used in access badges and inventory.
UPSUninterruptible Power Supply: Battery backup providing temporary power during outages, protecting equipment and allowing graceful shutdown.

Routing (4)

EIGRPEnhanced Interior Gateway Routing Protocol: Cisco advanced distance-vector routing protocol that uses DUAL algorithm for fast convergence.
IS-ISIntermediate System to Intermediate System: Link-state routing protocol used in large service provider networks, operating at Layer 2.
OSPFOpen Shortest Path First: Link-state interior gateway routing protocol using Dijkstra algorithm for IP networks, standard in enterprises.
RIPRouting Information Protocol: Distance-vector routing protocol using hop count as a metric, limited to 15 hops maximum.

Security Architecture (34)

BYODBring Your Own Device: Policy allowing employees to use personal devices to access organizational resources and data.
CASBCloud Access Security Broker: Security policy enforcement point between cloud consumers and providers, enforcing enterprise security policies.
CMDBConfiguration Management Database: Repository storing information about IT assets and their relationships, supporting change and asset management.
COPECorporate-Owned, Personally Enabled: Mobile device deployment model where the organization owns the device but allows limited personal use.
CSPCloud Service Provider: Organization that offers cloud computing services such as IaaS, PaaS, or SaaS.
CYODChoose Your Own Device: Mobile deployment model where employees select from a list of approved corporate devices.
DLPData Loss Prevention: Technology and policies that detect and prevent unauthorized exfiltration of sensitive data.
FaaSFunction as a Service: Serverless cloud model where the provider runs individual functions in response to events, scaling automatically.
FPGAField-Programmable Gate Array: Integrated circuit configured by the customer after manufacturing, used in specialized hardware applications.
HAHigh Availability: System design approach ensuring a service remains operational with minimal downtime, often using redundancy and failover.
IaaSInfrastructure as a Service: Cloud model providing virtualized computing resources like VMs, storage, and networking on demand.
ICSIndustrial Control System: Networked systems used to monitor and control industrial processes in critical infrastructure like power plants.
IoTInternet of Things: Network of physical devices with embedded sensors and connectivity that collect and exchange data.
MDMMobile Device Management: Software solution for enrolling, configuring, securing, and monitoring mobile devices in an organization.
MTBFMean Time Between Failures: Average time between system failures, used to measure reliability of repairable systems.
MTTFMean Time to Failure: Average time a non-repairable system operates before failure; used for components that are replaced, not repaired.
MTTRMean Time to Repair: Average time required to restore a failed system to operational status.
NFCNear Field Communication: Short-range wireless technology for contactless data exchange within approximately 4 cm.
OTOperational Technology: Hardware and software that detects or controls physical devices and processes in industrial environments.
PaaSPlatform as a Service: Cloud model providing a development platform with tools, middleware, and runtime managed by the provider.
PLCProgrammable Logic Controller: Industrial control computer used to automate manufacturing processes and equipment operations.
RTOSReal-Time Operating System: OS designed to process data and events within strict time constraints, used in embedded and industrial systems.
SaaSSoftware as a Service: Cloud model delivering fully managed applications accessible via a web browser.
SCADASupervisory Control and Data Acquisition: System for remote monitoring and control of industrial processes in critical infrastructure.
SELinuxSecurity-Enhanced Linux: Linux kernel security module providing mandatory access control policies for fine-grained permission enforcement.
SIMSubscriber Identity Module: Smart card storing mobile subscriber identity, authentication keys, and contacts for cellular access.
SPFSingle Point of Failure: Component whose failure would cause the entire system to stop functioning, addressed through redundancy.
TPMTrusted Platform Module: Hardware chip providing secure generation and storage of cryptographic keys, platform integrity attestation, and sealed storage.
UAVUnmanned Aerial Vehicle: Remotely operated or autonomous aircraft that poses physical security and surveillance risks.
UEMUnified Endpoint Management: Platform managing all endpoint types (mobile, desktop, IoT) from a single console with consistent policy enforcement.
VDIVirtual Desktop Infrastructure: Technology hosting desktop environments on a centralized server, with users accessing them remotely.
VMVirtual Machine: Software-emulated computer running its own OS on a hypervisor, isolated from the physical host.
VPCVirtual Private Cloud: Isolated virtual network within a public cloud environment with its own IP range, subnets, and security policies.
ZTNAZero Trust Network Access: Security model granting access based on continuous verification of identity, device, and context rather than network location.

Security Operations (29)

AISAutomated Indicator Sharing: DHS service enabling real-time exchange of machine-readable cyber threat indicators between organizations.
ATT&CKAdversarial Tactics, Techniques, and Common Knowledge: MITRE framework cataloging known adversary behaviors and tactics used in cyber intrusions.
AVAntivirus: Software that detects, prevents, and removes malicious software from systems.
CERTComputer Emergency Response Team: Team of security experts handling cybersecurity incidents and coordinating response efforts.
CIRTComputer Incident Response Team: Organizational team responsible for detecting, analyzing, and responding to security incidents.
CSIRTComputer Security Incident Response Team: Specialized team providing incident handling services including analysis, containment, and recovery.
DAMDatabase Activity Monitoring: Security technology that monitors and audits database access to detect unauthorized or suspicious queries.
EDREndpoint Detection and Response: Security solution that continuously monitors endpoints for suspicious activity and enables rapid investigation and response.
FIMFile Integrity Monitoring: Security control that detects unauthorized changes to critical system files and configurations.
HIDSHost-based Intrusion Detection System: Security agent monitoring a single host for suspicious activity, file changes, and policy violations.
HIPSHost-based Intrusion Prevention System: Security agent that monitors and can block malicious activity on a host in real time.
IDSIntrusion Detection System: Security system that monitors network or host activity for malicious behavior and generates alerts.
IoCIndicator of Compromise: Forensic artifact or observable that suggests a system has been breached, such as unusual traffic or file hashes.
IPSIntrusion Prevention System: Inline security system that monitors, detects, and actively blocks malicious network activity.
IRIncident Response: Organized approach to detecting, managing, and recovering from cybersecurity incidents.
MDRManaged Detection and Response: Outsourced security service providing 24/7 threat monitoring, detection, and incident response.
NIDSNetwork-based Intrusion Detection System: System monitoring network traffic for suspicious patterns and generating alerts for potential intrusions.
NIPSNetwork-based Intrusion Prevention System: Inline system that monitors network traffic and actively blocks detected threats in real time.
OSINTOpen-Source Intelligence: Intelligence collected from publicly available sources such as websites, social media, and public records.
OVALOpen Vulnerability and Assessment Language: Standardized XML language for expressing security vulnerability assessment and configuration data.
SIEMSecurity Information and Event Management: Platform aggregating and correlating log data from across the environment to detect threats and support incident response.
SOARSecurity Orchestration, Automation, and Response: Platform that integrates security tools and automates incident response workflows to reduce analyst workload.
SOCSecurity Operations Center: Centralized team and facility that monitors, detects, analyzes, and responds to cybersecurity incidents 24/7.
STIXStructured Threat Information eXpression: Standardized language for describing cyber threat information in a structured, machine-readable format.
SYSLOGSystem Logging Protocol: Standard protocol for forwarding log messages from network devices to a centralized logging server on UDP port 514.
TAXIITrusted Automated eXchange of Intelligence Information: Transport protocol for sharing STIX cyber threat intelligence data between organizations.
WIDSWireless Intrusion Detection System: System monitoring wireless network traffic for unauthorized access points and suspicious activity.
WIPSWireless Intrusion Prevention System: System that detects and automatically mitigates wireless threats like rogue access points.
XDRExtended Detection and Response: Security platform integrating data from endpoints, networks, and cloud to provide unified threat detection and response.

Security Program Management (33)

ALEAnnualized Loss Expectancy: Expected monetary loss from a risk per year, calculated as SLE multiplied by ARO.
AROAnnualized Rate of Occurrence: Estimated frequency of a threat occurring within a single year, used in quantitative risk analysis.
AUPAcceptable Use Policy: Organizational policy defining permitted and prohibited uses of IT systems and data.
BCPBusiness Continuity Planning: Process of creating plans to ensure critical business functions continue during and after a disaster.
BPABusiness Partnership Agreement: Legal document defining terms, responsibilities, and expectations between business partners.
CCPACalifornia Consumer Privacy Act: California law granting consumers rights over their personal data and imposing obligations on businesses.
CISCenter for Internet Security: Nonprofit organization publishing security benchmarks, best practices, and the CIS Controls framework.
CISOChief Information Security Officer: Senior executive responsible for an organization's information security strategy and program.
CTOChief Technology Officer: Senior executive overseeing an organization's technology strategy and development.
DBADatabase Administrator: Role responsible for managing, securing, and maintaining database systems.
DPOData Protection Officer: Role required by GDPR to oversee data protection strategy, compliance, and data subject requests.
DRPDisaster Recovery Plan: Documented process for restoring IT infrastructure and operations after a catastrophic event.
GDPRGeneral Data Protection Regulation: EU regulation governing the collection, processing, and protection of personal data for EU residents.
HIPAAHealth Insurance Portability and Accountability Act: US law establishing standards for protecting sensitive patient health information.
ISAInterconnection Security Agreement: Agreement documenting the technical security requirements for connecting two organizations' IT systems.
ISOInternational Organization for Standardization: International body developing standards including ISO 27001 for information security management systems.
ISSOInformation Systems Security Officer: Role responsible for ensuring the security of a specific information system and its compliance with policies.
KPIKey Performance Indicator: Measurable value demonstrating how effectively an organization achieves key business or security objectives.
KRIKey Risk Indicator: Metric used to provide an early warning signal of increasing risk exposure in an organization.
MOUMemorandum of Understanding: Non-binding agreement between organizations outlining mutual intentions and expectations for cooperation.
MSAMaster Service Agreement: Contract establishing the terms governing future transactions or agreements between parties.
NDANon-Disclosure Agreement: Legal contract preventing parties from sharing confidential information with unauthorized persons.
NISTNational Institute of Standards and Technology: US federal agency that develops cybersecurity frameworks, standards, and guidelines.
NIST CSFNIST Cybersecurity Framework: Voluntary framework of standards and best practices organized into Identify, Protect, Detect, Respond, and Recover functions.
PCI-DSSPayment Card Industry Data Security Standard: Security standard for organizations handling credit card data, mandating controls for cardholder data protection.
PHIProtected Health Information: Individually identifiable health information regulated by HIPAA, requiring safeguards for privacy.
PIIPersonally Identifiable Information: Data that can be used to identify a specific individual, such as SSN, full name, or biometric records.
RPORecovery Point Objective: Maximum acceptable amount of data loss measured in time, defining backup frequency requirements.
RTORecovery Time Objective: Maximum acceptable downtime before a business function must be restored after a disruption.
SLAService Level Agreement: Contract defining measurable service targets like uptime, response time, and support levels between provider and client.
SLESingle Loss Expectancy: Monetary value of loss from a single occurrence of a specific risk event.
SOWStatement of Work: Document defining the specific tasks, deliverables, and timelines for a project or service engagement.
SOXSarbanes-Oxley Act: US federal law mandating financial reporting controls and auditing requirements for publicly traded companies.

Threats and Vulnerabilities (9)

APTAdvanced Persistent Threat: Sophisticated, long-term cyberattack where an intruder gains and maintains unauthorized access, typically state-sponsored.
CVECommon Vulnerabilities and Exposures: Standardized catalog of publicly known cybersecurity vulnerabilities, each assigned a unique identifier.
CVSSCommon Vulnerability Scoring System: Open framework for rating the severity of security vulnerabilities on a 0-10 scale.
DDoSDistributed Denial of Service: Attack using multiple compromised systems to flood a target, overwhelming its capacity to serve legitimate requests.
DoSDenial of Service: Attack that disrupts a service by overwhelming it with traffic or exploiting a vulnerability to make it unavailable.
MaaSMalware as a Service: Criminal business model where threat actors sell or lease malware kits to less-skilled attackers.
MITMMan-in-the-Middle: Attack where an adversary secretly intercepts and potentially alters communication between two parties.
RaaSRansomware as a Service: Criminal business model where ransomware developers license their tools to affiliates in exchange for a cut of ransom payments.
TTPTactics, Techniques, and Procedures: Patterns of behavior and methods used by threat actors, forming the basis for threat intelligence analysis.

Memorize acronyms by using them

Acronyms stick when you apply them. Practice real exam questions free — every missed one becomes a spaced-repetition flashcard.

Start Free Practice Test