Reference
Acronyms glossary
Every acronym on the CompTIA Security+ SY0-701 exam, expanded and explained. Search by acronym, full term, or what it means.
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331/331 acronyms
A
- AAAAuthentication, Authorization, and AccountingThe framework for controlling access: prove who you are, decide what you can do, and record what you did.
- ACLAccess Control ListAn ordered set of rules that permits or denies traffic or access to a resource.
- AESAdvanced Encryption StandardThe widely used symmetric block cipher that replaced DES, available in 128, 192, and 256-bit keys.
- AES-256Advanced Encryption Standard 256-bitAES using a 256-bit key, the strongest standard AES variant.
- AHAuthentication HeaderThe IPSec protocol that provides integrity and authentication but not confidentiality.
- AIArtificial IntelligenceSystems that perform tasks normally requiring human reasoning, increasingly used by both defenders and attackers.
- AISAutomated Indicator SharingA capability that lets organizations exchange cyber threat indicators in real time.
- ALEAnnualized Loss ExpectancyThe expected yearly cost of a risk, calculated as SLE multiplied by ARO.
- APAccess PointA device that lets wireless clients connect to a wired network.
- APIApplication Programming InterfaceA defined interface that lets software components talk to each other; a common attack surface.
- APTAdvanced Persistent ThreatA well-resourced, stealthy adversary (often nation-state) that maintains long-term access.
- AROAnnualized Rate of OccurrenceHow many times per year a given risk is expected to happen.
- ARPAddress Resolution ProtocolMaps IP addresses to MAC addresses on a local network; spoofable for on-path attacks.
- ASLRAddress Space Layout RandomizationA memory protection that randomizes process address layout to hinder exploitation.
- ATT&CKAdversarial Tactics, Techniques, and Common KnowledgeThe MITRE knowledge base of real-world attacker behaviors used for detection and mapping.
- AUPAcceptable Use PolicyA policy defining how employees may use organizational systems and data.
- AVAntivirusSoftware that detects and removes malware, traditionally using signatures.
B
- BASHBourne Again ShellA common Unix and Linux command shell often abused in scripting-based attacks.
- BCPBusiness Continuity PlanThe plan for keeping critical business functions running during and after a disruption.
- BGPBorder Gateway ProtocolThe routing protocol of the internet; route hijacking targets it.
- BIABusiness Impact AnalysisThe process that identifies critical functions and the impact of their loss, producing RTO and RPO.
- BIOSBasic Input/Output SystemLegacy firmware that initializes hardware at boot, largely replaced by UEFI.
- BPABusiness Partners AgreementA contract defining the terms and responsibilities between business partners.
- BPDUBridge Protocol Data UnitSpanning Tree Protocol messages; BPDU Guard protects against rogue switches.
- BYODBring Your Own DeviceA model allowing personal devices for work, raising data and management concerns.
C
- CACertificate AuthorityA trusted entity that issues and signs digital certificates in a PKI.
- CAPTCHACompletely Automated Public Turing Test to Tell Computers and Humans ApartA challenge that distinguishes humans from bots to limit automation abuse.
- CARCorrective Action ReportA document recording the steps taken to fix a problem and prevent recurrence.
- CASBCloud Access Security BrokerA control point between users and cloud services that enforces security policy.
- CBCCipher Block ChainingA block cipher mode where each block is XORed with the previous ciphertext block.
- CCMPCounter Mode/CBC-MAC ProtocolThe AES-based encryption protocol used by WPA2.
- CCTVClosed-Circuit TelevisionVideo surveillance, a physical detective and deterrent control.
- CERTComputer Emergency Response TeamA team that responds to and coordinates handling of security incidents.
- CFBCipher FeedbackA block cipher mode that turns a block cipher into a self-synchronizing stream cipher.
- CHAPChallenge Handshake Authentication ProtocolAn authentication protocol that verifies identity using a periodic challenge and response.
- CIAConfidentiality, Integrity, and AvailabilityThe core triad of information security goals.
- CIOChief Information OfficerThe executive responsible for information technology strategy and operations.
- CIRTComputer Incident Response TeamThe designated team that detects, analyzes, and responds to security incidents.
- CMSContent Management SystemSoftware for creating and managing digital content, such as a website platform.
- COOPContinuity of Operations PlanA plan ensuring essential functions continue during a wide range of emergencies.
- COPECorporate-Owned, Personally EnabledA device model where the company owns the device but allows personal use.
- CPContingency PlanningPreparing alternative courses of action for adverse events.
- CRCCyclic Redundancy CheckAn error-detecting code that checks data integrity in transit or storage.
- CRLCertificate Revocation ListA published list of certificates a CA has revoked before their expiry.
- CSOChief Security OfficerThe executive accountable for the overall security of an organization.
- CSPCloud Service ProviderA vendor that delivers computing services over the internet, such as IaaS or SaaS.
- CSRCertificate Signing RequestA request containing a public key and identity, submitted to a CA to obtain a certificate.
- CSRFCross-Site Request ForgeryAn attack that tricks an authenticated user into submitting unwanted requests.
- CSUChannel Service UnitA device connecting a terminal to a digital line, often paired with a DSU.
- CTMCounter ModeA block cipher mode that turns a block cipher into a stream cipher by encrypting successive counter values.
- CTOChief Technology OfficerThe executive responsible for technology direction and engineering.
- CVECommon Vulnerabilities and ExposuresA standardized identifier for a publicly known vulnerability.
- CVSSCommon Vulnerability Scoring SystemA framework that rates vulnerability severity on a 0 to 10 scale.
- CYODChoose Your Own DeviceA model letting employees pick a work device from an approved list.
D
- DACDiscretionary Access ControlAn access model where resource owners decide who gets access.
- DBADatabase AdministratorThe role responsible for managing and securing databases.
- DDoSDistributed Denial-of-ServiceA flood of traffic from many sources that overwhelms a target service.
- DEPData Execution PreventionA memory protection that marks regions non-executable to block code injection.
- DESData Encryption StandardAn obsolete 56-bit symmetric cipher, broken by modern brute force.
- DHCPDynamic Host Configuration ProtocolAutomatically assigns IP addresses and network settings to hosts.
- DHEDiffie-Hellman EphemeralA key exchange that generates a fresh key per session for forward secrecy.
- DKIMDomainKeys Identified MailAn email authentication method that signs messages to prove domain origin.
- DLLDynamic Link LibraryShared Windows code modules; DLL injection and sideloading are common attacks.
- DLPData Loss PreventionTechnology that detects and blocks unauthorized movement of sensitive data.
- DMARCDomain-based Message Authentication, Reporting, and ConformanceAn email policy framework built on SPF and DKIM to fight spoofing.
- DNATDestination Network Address TranslationRewrites the destination address of packets, often for port forwarding.
- DNSDomain Name SystemResolves human-readable names to IP addresses; a frequent attack and exfiltration channel.
- DNSSECDomain Name System Security ExtensionsAdds cryptographic signatures to DNS to prevent spoofing and cache poisoning.
- DoSDenial-of-ServiceAn attack that makes a resource unavailable to legitimate users.
- DPOData Protection OfficerThe role accountable for an organization's data privacy compliance.
- DRPDisaster Recovery PlanThe plan for restoring IT systems and data after a major disruption.
- DSADigital Signature AlgorithmA standard for generating and verifying digital signatures.
- DSLDigital Subscriber LineA broadband technology that carries data over ordinary copper telephone lines.
E
- EAPExtensible Authentication ProtocolA flexible authentication framework widely used in wireless and 802.1X.
- ECBElectronic CodebookA weak block cipher mode that encrypts identical blocks identically, leaking patterns.
- ECCElliptic Curve CryptographyPublic-key cryptography offering strong security with smaller keys.
- ECDHEElliptic Curve Diffie-Hellman EphemeralAn ephemeral key exchange using elliptic curves for forward secrecy.
- ECDSAElliptic Curve Digital Signature AlgorithmA digital signature algorithm based on elliptic curve cryptography.
- EDREndpoint Detection and ResponseTooling that monitors endpoints for threats and supports investigation and response.
- EFSEncrypting File SystemA Windows feature that encrypts individual files and folders.
- ERPEnterprise Resource PlanningIntegrated software managing core business processes such as finance and HR.
- ESNElectronic Serial NumberA unique identifier assigned to a mobile device.
- ESPEncapsulating Security PayloadThe IPSec protocol that provides confidentiality, integrity, and authentication.
F
- FACLFile System Access Control ListPer-file or per-directory permissions that control access at the filesystem level.
- FARFalse Acceptance RateIn biometrics, the rate at which unauthorized users are wrongly accepted.
- FDEFull Disk EncryptionEncryption of an entire drive so data is protected at rest.
- FIMFile Integrity MonitoringDetects unauthorized changes to critical files by comparing against a baseline.
- FPGAField Programmable Gate ArrayA reconfigurable hardware chip used in specialized and embedded systems.
- FRRFalse Rejection RateIn biometrics, the rate at which legitimate users are wrongly denied.
- FTPFile Transfer ProtocolA legacy file transfer protocol that sends credentials and data in cleartext.
- FTPSFile Transfer Protocol SecureFTP wrapped in TLS for encrypted file transfer.
G
- GCMGalois/Counter ModeAn authenticated encryption mode providing both confidentiality and integrity.
- GDPRGeneral Data Protection RegulationThe European Union regulation governing personal data protection and privacy.
- GPGGNU Privacy GuardAn open-source implementation of the OpenPGP standard for encryption and signing.
- GPOGroup Policy ObjectA Windows mechanism for centrally configuring users and computers in a domain.
- GPSGlobal Positioning SystemSatellite-based location service; spoofing can mislead navigation and geofencing.
- GPUGraphics Processing UnitA parallel processor; often used to accelerate password cracking.
- GREGeneric Routing EncapsulationA tunneling protocol that encapsulates many network layer protocols.
H
- HAHigh AvailabilityDesigning systems for minimal downtime through redundancy and failover.
- HDDHard Disk DriveA magnetic storage device; secure disposal requires wiping or destruction.
- HIDSHost-based Intrusion Detection SystemSoftware on a host that detects suspicious activity and alerts.
- HIPSHost-based Intrusion Prevention SystemHost software that detects and actively blocks malicious activity.
- HMACHash-based Message Authentication CodeA keyed hash that verifies both integrity and authenticity of a message.
- HOTPHMAC-based One-Time PasswordA one-time password generated from a counter and a shared secret.
- HSMHardware Security ModuleA tamper-resistant device that generates, stores, and manages cryptographic keys.
- HTMLHypertext Markup LanguageThe markup language for web pages; a vector for injection when unsanitized.
- HTTPHypertext Transfer ProtocolThe cleartext protocol for web traffic on port 80.
- HTTPSHypertext Transfer Protocol SecureHTTP secured with TLS on port 443.
- HVACHeating, Ventilation, and Air ConditioningEnvironmental controls; a target as an OT system and a data-center dependency.
I
- IaaSInfrastructure as a ServiceA cloud model providing virtual machines, storage, and networking.
- IaCInfrastructure as CodeManaging infrastructure through machine-readable definition files.
- IAMIdentity and Access ManagementThe discipline of managing digital identities and their access rights.
- ICMPInternet Control Message ProtocolA network diagnostic protocol used by ping; abused for scanning and floods.
- ICSIndustrial Control SystemSystems that control industrial processes, often fragile and long-lived.
- IDEAInternational Data Encryption AlgorithmA 64-bit-block symmetric cipher with a 128-bit key, historically used in early PGP.
- IDFIntermediate Distribution FrameA wiring closet that connects end devices back to the main distribution frame.
- IdPIdentity ProviderA service that authenticates users and asserts identity to relying parties.
- IDSIntrusion Detection SystemMonitors traffic or hosts and alerts on suspected malicious activity.
- IEEEInstitute of Electrical and Electronics EngineersA standards body responsible for protocols such as 802.1X and 802.11.
- IKEInternet Key ExchangeThe protocol that negotiates security associations and keys for IPSec.
- IMInstant MessagingReal-time text communication; a channel for phishing and data leakage.
- IMAPInternet Message Access ProtocolA protocol for retrieving and managing email on a server.
- IoCIndicators of CompromiseForensic artifacts, such as hashes or IPs, that signal a breach.
- IoTInternet of ThingsNetworked everyday devices that often lack strong security controls.
- IPInternet ProtocolThe core protocol for addressing and routing packets across networks.
- IPSIntrusion Prevention SystemInspects traffic inline and blocks detected threats.
- IPSecInternet Protocol SecurityA suite that authenticates and encrypts IP traffic, used for VPNs.
- IRIncident ResponseThe organized approach to handling and recovering from security incidents.
- IRCInternet Relay ChatA chat protocol historically used for botnet command and control.
- IRPIncident Response PlanThe documented procedures for detecting and handling incidents.
- ISOInternational Organization for StandardizationA body that publishes standards such as the ISO 27000 security series.
- ISPInternet Service ProviderA company that provides internet connectivity.
- ISSOInformation Systems Security OfficerThe role responsible for the security of a specific information system.
- IVInitialization VectorA random value that ensures identical plaintext encrypts differently each time.
K
L
- L2TPLayer 2 Tunneling ProtocolA VPN tunneling protocol usually paired with IPSec for encryption.
- LANLocal Area NetworkA network covering a small area such as an office or building.
- LDAPLightweight Directory Access ProtocolA protocol for querying and modifying directory services like Active Directory.
- LEAPLightweight Extensible Authentication ProtocolA Cisco EAP variant now considered weak and deprecated.
M
- MaaSMonitoring as a ServiceCloud-delivered monitoring of systems and security events.
- MACMandatory Access ControlAn access model where the system enforces access based on labels and clearances.
- MAC (address)Media Access Control AddressA hardware identifier for a network interface; spoofable to bypass filtering.
- MAC (message)Message Authentication CodeA short tag that verifies a message's integrity and authenticity.
- MANMetropolitan Area NetworkA network spanning a city or large campus.
- MBRMaster Boot RecordThe first sector of a legacy-partitioned disk that holds boot code and the partition table.
- MD5Message Digest 5A 128-bit cryptographic hash function that is now broken and must not be used for security.
- MDFMain Distribution FrameThe central wiring point where external lines meet internal cabling.
- MDMMobile Device ManagementSoftware for centrally enforcing policy on mobile devices.
- MFAMultifactor AuthenticationAuthentication using two or more distinct factor types.
- MFDMultifunction DeviceA combined printer, scanner, and copier that is also a network endpoint.
- MFPMultifunction PrinterA networked printer with scanning and faxing; an often-overlooked attack surface.
- MLMachine LearningA subset of AI where systems learn patterns from data, used in detection and attacks.
- MMSMultimedia Messaging ServiceA messaging standard for sending media; a mobile attack vector.
- MOAMemorandum of AgreementA formal agreement defining roles and responsibilities between parties.
- MOUMemorandum of UnderstandingA non-binding statement of intent between parties.
- MPLSMultiprotocol Label SwitchingA high-performance routing technique using labels rather than addresses.
- MSAMaster Service AgreementAn overarching contract setting general terms for future engagements.
- MSCHAPMicrosoft Challenge Handshake Authentication ProtocolA Microsoft authentication protocol using a challenge and response, now considered weak.
- MSPManaged Service ProviderA vendor that remotely manages a customer's IT infrastructure.
- MSSPManaged Security Service ProviderA vendor that delivers outsourced monitoring and security management.
- MTBFMean Time Between FailuresThe average operating time between failures of a repairable system.
- MTTFMean Time to FailureThe average lifespan of a non-repairable component.
- MTTRMean Time to RepairThe average time required to restore a failed system.
- MTUMaximum Transmission UnitThe largest packet size a network link can carry without fragmentation.
N
- NACNetwork Access ControlEnforces policy on devices before granting network access.
- NATNetwork Address TranslationMaps private addresses to public ones, hiding internal hosts.
- NDANon-Disclosure AgreementA contract that legally protects shared confidential information.
- NFCNear Field CommunicationVery short-range wireless used for contactless payments and pairing.
- NGFWNext-Generation FirewallA firewall adding deep inspection, application awareness, and IPS.
- NIDSNetwork-based Intrusion Detection SystemMonitors network traffic for malicious activity and alerts.
- NIPSNetwork-based Intrusion Prevention SystemInspects network traffic inline and blocks threats.
- NISTNational Institute of Standards and TechnologyA US agency that publishes widely used security frameworks and guidance.
- NTFSNew Technology File SystemThe Windows file system supporting permissions, encryption, and auditing.
- NTLMNew Technology LAN ManagerA legacy Windows authentication protocol vulnerable to relay and pass-the-hash.
- NTPNetwork Time ProtocolSynchronizes clocks across systems, critical for logging and certificates.
O
- OAuthOpen AuthorizationA standard that delegates access to resources without sharing credentials.
- OCSPOnline Certificate Status ProtocolA real-time protocol for checking whether a certificate is revoked.
- OIDObject IdentifierA globally unique identifier used in certificates and directory schemas.
- OSOperating SystemThe software that manages hardware and runs applications.
- OSINTOpen-Source IntelligenceIntelligence gathered from publicly available sources.
- OSPFOpen Shortest Path FirstA link-state interior routing protocol.
- OTOperational TechnologyHardware and software that monitors and controls physical processes.
- OTAOver-the-AirWireless delivery of updates or configuration to devices.
- OVALOpen Vulnerability and Assessment LanguageA standardized XML language for describing system state to test for vulnerabilities and configuration.
P
- P12PKCS #12A file format that bundles a private key with its certificate chain, usually password protected.
- P2PPeer-to-PeerA decentralized network model; a channel for data leakage and malware.
- PaaSPlatform as a ServiceA cloud model providing a managed platform for building applications.
- PACProxy Auto ConfigurationA file that tells browsers which proxy to use for given URLs.
- PAMPrivileged Access ManagementControls and monitors elevated accounts, often with vaulting and just-in-time access.
- PAM (modules)Pluggable Authentication ModulesA Unix and Linux framework for integrating authentication methods.
- PAPPassword Authentication ProtocolA legacy authentication protocol that transmits passwords in cleartext.
- PATPort Address TranslationNAT variant that maps many private hosts to one public IP using ports.
- PBKDF2Password-Based Key Derivation Function 2A key-stretching function that hashes a password many times with a salt to slow brute-force attacks.
- PBXPrivate Branch ExchangeAn internal telephone switching system, a target for toll fraud.
- PCAPPacket CaptureA recorded set of network packets used for analysis and forensics.
- PCI DSSPayment Card Industry Data Security StandardThe security standard for organizations handling payment card data.
- PDUPower Distribution UnitA device distributing electrical power within a rack or data center.
- PEAPProtected Extensible Authentication ProtocolAn EAP method that wraps authentication inside a TLS tunnel.
- PEDPersonal Electronic DeviceA personally owned gadget that may introduce risk in the workplace.
- PEMPrivacy Enhanced MailA base64 certificate and key file format widely used in PKI.
- PFSPerfect Forward SecrecyA property ensuring past sessions stay secure even if a long-term key leaks.
- PGPPretty Good PrivacyAn encryption program for securing email and files.
- PHIProtected Health InformationHealth data regulated under laws such as HIPAA.
- PIIPersonally Identifiable InformationData that can identify a specific individual.
- PIVPersonal Identity VerificationA US government smart card standard for identity and access.
- PKCSPublic Key Cryptography StandardsA set of standards defining key and certificate formats.
- PKIPublic Key InfrastructureThe system of CAs, certificates, and keys that enables public-key trust.
- POPPost Office ProtocolA protocol for downloading email from a server to a client.
- POTSPlain Old Telephone ServiceThe traditional analog telephone network.
- PPPPoint-to-Point ProtocolA protocol for direct connections between two network nodes.
- PPTPPoint-to-Point Tunneling ProtocolAn obsolete VPN protocol with known cryptographic weaknesses.
- PSKPre-Shared KeyA secret shared in advance to authenticate or encrypt, as in WPA2-PSK.
- PTZPan-Tilt-ZoomA camera that can rotate horizontally and vertically and zoom, often remotely controlled.
- PUPPotentially Unwanted ProgramSoftware bundled with a download that is not outright malware but is undesirable.
R
- RARegistration AuthorityA PKI entity that verifies identities before a CA issues certificates.
- RACEResearch and Development in Advanced Communications Technologies in EuropeThe European research programme that gave RIPEMD the first word of its name.
- RADRapid Application DevelopmentA software model that favors fast prototyping and iteration over heavy up-front planning.
- RADIUSRemote Authentication Dial-In User ServiceA centralized AAA protocol for network access.
- RAIDRedundant Array of Independent DisksCombines disks for redundancy or performance.
- RASRemote Access ServerA server that provides remote users access to a network.
- RATRemote Access TrojanMalware that gives an attacker covert remote control of a host.
- RBACRole-Based Access ControlAccess granted based on a user's assigned role.
- RBAC (rule)Rule-Based Access ControlAccess decided by system-enforced rules such as ACL conditions.
- RC4Rivest Cipher 4A deprecated stream cipher with known weaknesses.
- RDPRemote Desktop ProtocolA Microsoft protocol for remote graphical access, a frequent attack target.
- RFIDRadio Frequency IdentificationWireless tags used for tracking and access badges; cloneable.
- RIPEMDRACE Integrity Primitives Evaluation Message DigestA family of cryptographic hash functions developed in Europe, with RIPEMD-160 the best known.
- ROIReturn on InvestmentA measure of the financial benefit of an investment relative to its cost.
- RPORecovery Point ObjectiveThe maximum acceptable amount of data loss measured in time.
- RSARivest-Shamir-AdlemanA widely used public-key algorithm for encryption and signatures.
- RTBHRemotely Triggered Black HoleA technique that drops attack traffic by routing it to a null destination, often to blunt DDoS.
- RTORecovery Time ObjectiveThe maximum acceptable time to restore a function after disruption.
- RTOSReal-Time Operating SystemAn OS for time-critical embedded and control systems.
- RTPReal-Time Transport ProtocolA protocol for delivering audio and video streams over IP networks.
S
- S/MIMESecure/Multipurpose Internet Mail ExtensionsA standard for signing and encrypting email using certificates.
- SaaSSoftware as a ServiceA cloud model delivering applications over the internet.
- SAESimultaneous Authentication of EqualsThe WPA3 handshake that resists offline password cracking.
- SAMLSecurity Assertion Markup LanguageAn XML standard for exchanging authentication and authorization data for SSO.
- SANSubject Alternative Name / Storage Area NetworkA certificate field listing extra identities, or a dedicated high-speed block-storage network.
- SASESecure Access Service EdgeA cloud model combining networking and security functions at the edge.
- SCADASupervisory Control and Data AcquisitionSystems that monitor and control large-scale industrial processes.
- SCAPSecurity Content Automation ProtocolA suite of standards for automating vulnerability and configuration assessment.
- SCEPSimple Certificate Enrollment ProtocolA protocol that automates issuing and renewing device certificates at scale.
- SD-WANSoftware-Defined Wide Area NetworkCentralized, software-driven control of WAN connectivity.
- SDKSoftware Development KitTools and libraries for building applications on a platform.
- SDLCSoftware Development LifecycleThe structured process for building and maintaining software securely.
- SDLMSoftware Development Lifecycle MethodologyThe structured process of planning, building, testing, deploying, and maintaining software securely.
- SDNSoftware-Defined NetworkingSeparating the network control plane from the data plane for programmability.
- SE LinuxSecurity-Enhanced LinuxA Linux kernel feature enforcing mandatory access control policies on processes and files.
- SEDSelf-Encrypting DriveA drive that automatically encrypts data in hardware.
- SEHStructured Exception HandlerA Windows error-handling mechanism that can be abused in exploits.
- SFTPSecure File Transfer ProtocolFile transfer carried over SSH for confidentiality and integrity.
- SHASecure Hash AlgorithmA family of cryptographic hash functions, with SHA-2 and SHA-3 recommended.
- SHTTPSecure Hypertext Transfer ProtocolAn obsolete protocol for securing individual web messages, superseded by HTTPS over TLS.
- SIEMSecurity Information and Event ManagementAggregates and correlates logs for monitoring, alerting, and investigation.
- SIMSubscriber Identity ModuleA chip identifying a mobile subscriber; targeted by SIM-swapping.
- SLAService Level AgreementA contract defining expected service levels and remedies.
- SLESingle Loss ExpectancyThe monetary loss expected from a single occurrence of a risk.
- SMSShort Message ServiceText messaging; a weak MFA channel and a smishing vector.
- SMTPSimple Mail Transfer ProtocolThe protocol for sending email between servers.
- SMTPSSimple Mail Transfer Protocol SecureSMTP secured with TLS.
- SNMPSimple Network Management ProtocolA protocol for monitoring and managing network devices.
- SOAPSimple Object Access ProtocolAn XML-based messaging protocol for web services.
- SOARSecurity Orchestration, Automation, and ResponsePlatforms that automate and coordinate security operations with playbooks.
- SoCSystem on ChipAn integrated circuit combining CPU, memory, and peripherals on one chip.
- SOCSecurity Operations CenterThe team and facility that monitors and defends against threats continuously.
- SOWStatement of WorkA document defining deliverables, timelines, and scope of a project.
- SPFSender Policy FrameworkAn email standard that lists which servers may send for a domain.
- SPIMSpam over Instant MessagingUnsolicited messages delivered through instant messaging platforms.
- SQLStructured Query LanguageThe language for querying relational databases; injection abuses it.
- SQLiSQL InjectionAn attack that injects malicious SQL through unsanitized input.
- SRTPSecure Real-Time Transport ProtocolEncrypts and authenticates voice and video media streams.
- SSDSolid State DriveFlash-based storage; wear leveling complicates secure erasure.
- SSHSecure ShellAn encrypted protocol for remote administration and tunneling.
- SSLSecure Sockets LayerThe deprecated predecessor to TLS for encrypting connections.
- SSOSingle Sign-OnAuthenticating once to access multiple systems.
- STIXStructured Threat Information eXpressionA standardized language for describing cyber threat intelligence.
- STPShielded Twisted PairCabling with shielding to reduce electromagnetic interference.
- SWGSecure Web GatewayA control that filters and inspects web traffic to enforce policy.
T
- TACACS+Terminal Access Controller Access Control System PlusA Cisco AAA protocol that separates authentication, authorization, and accounting.
- TAXIITrusted Automated eXchange of Indicator InformationA transport protocol for sharing STIX threat intelligence.
- TCPTransmission Control ProtocolA reliable, connection-oriented transport protocol.
- TCP/IPTransmission Control Protocol/Internet ProtocolThe layered protocol suite the internet runs on, named for its two core protocols.
- TGTTicket Granting TicketA Kerberos credential used to request service tickets; targeted by Golden Ticket attacks.
- TKIPTemporal Key Integrity ProtocolA deprecated WPA encryption protocol replaced by CCMP.
- TLSTransport Layer SecurityThe standard protocol for encrypting network connections.
- TOCTime-of-CheckThe moment a system verifies a condition, the first half of a TOCTOU race condition.
- TOTPTime-based One-Time PasswordA one-time code derived from the current time and a shared secret.
- TOUTime-of-UseThe moment a system acts on a condition, the second half of a TOCTOU race condition.
- TPMTrusted Platform ModuleA hardware chip that securely stores keys and supports measured boot.
- TSIGTransaction SignatureA shared-key mechanism that authenticates DNS messages such as zone transfers and updates.
- TTPTactics, Techniques, and ProceduresThe behavior patterns that characterize a threat actor.
U
- UATUser Acceptance TestingFinal testing by users to confirm software meets requirements.
- UAVUnmanned Aerial VehicleA drone; a physical reconnaissance and delivery threat.
- UDPUser Datagram ProtocolA fast, connectionless transport protocol used in floods and amplification.
- UEBAUser and Entity Behavior AnalyticsDetects threats by flagging deviations from normal behavior baselines.
- UEFIUnified Extensible Firmware InterfaceModern firmware replacing BIOS, supporting Secure Boot.
- UEMUnified Endpoint ManagementA single platform for managing all endpoint types.
- UPSUninterruptible Power SupplyA battery backup that maintains power during short outages.
- URIUniform Resource IdentifierA string that identifies a resource, of which a URL is one form.
- URLUniform Resource LocatorA web address; manipulated in phishing and redirection attacks.
- USBUniversal Serial BusA common peripheral connector; a vector for malware and data theft.
- USB OTGUSB On-the-GoA feature letting a device act as host to other USB devices.
- UTMUnified Threat ManagementAn all-in-one appliance bundling firewall, IPS, antivirus, and more.
- UTPUnshielded Twisted PairCommon network cabling without electromagnetic shielding.
V
- VBAVisual Basic for ApplicationsA macro language in Office documents, abused to deliver malware.
- VDEVirtual Desktop EnvironmentA desktop that runs on centralized infrastructure and is accessed remotely from a thin client.
- VDIVirtual Desktop InfrastructureHosting desktops on centralized servers and streaming them to users.
- VLANVirtual Local Area NetworkA logical network segment that isolates traffic on shared switches.
- VLSMVariable Length Subnet MaskingSubnetting with masks of differing lengths for efficient address use.
- VMVirtual MachineA software-emulated computer; escape attacks target the hypervisor boundary.
- VoIPVoice over Internet ProtocolCarrying voice calls over IP networks.
- VPCVirtual Private CloudAn isolated, logically private section of a public cloud.
- VPNVirtual Private NetworkAn encrypted tunnel that extends a private network across a public one.
- VTCVideo TeleconferencingReal-time video and audio meetings between remote participants over a network.
W
- WAFWeb Application FirewallFilters HTTP traffic to protect web apps from injection and similar attacks.
- WAPWireless Access PointA device that bridges wireless clients to a wired network.
- WEPWired Equivalent PrivacyAn obsolete, easily broken Wi-Fi encryption standard.
- WIDSWireless Intrusion Detection SystemMonitors the wireless spectrum for rogue devices and attacks.
- WIPSWireless Intrusion Prevention SystemDetects and actively blocks wireless threats such as rogue APs.
- WOWork OrderA document authorizing and scoping specific work, often issued under a master agreement.
- WPAWi-Fi Protected AccessA family of Wi-Fi security standards; WPA3 is current.
- WPSWi-Fi Protected SetupA simplified Wi-Fi setup feature with known PIN brute-force weaknesses.
- WTLSWireless Transport Layer SecurityThe security layer of the legacy Wireless Application Protocol stack for mobile devices.
X
- XDRExtended Detection and ResponseCorrelates detection and response across endpoints, network, and cloud.
- XMLExtensible Markup LanguageA structured data format; XXE and injection target its parsers.
- XORExclusive ORA bitwise operation fundamental to many ciphers.
- XSRFCross-Site Request ForgeryAnother name for CSRF, forcing an authenticated user to make unwanted requests.
- XSSCross-Site ScriptingInjecting malicious scripts into web pages viewed by other users.
Z
Compare and contrast
Knowing what an acronym expands to is not the same as knowing when the exam wants one and not the other. These break down the pairs that get confused most.
- IDS vs IPS
- Symmetric vs asymmetric encryption
- Authentication vs authorization
- Hashing vs encryption
- TCP vs UDP
- Vulnerability vs threat vs risk
- MAC vs DAC vs RBAC
- Security+ vs Network+
- Security+ vs CySA+
- Security+ vs CISSP
- Security+ vs A+
- Security+ vs CEH
- TLS vs SSL
- SIEM vs SOAR
- RTO vs RPO
- WPA2 vs WPA3
- Vulnerability scan vs penetration test
- Red team vs blue team vs purple team
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