Glossary
The vocabulary of identity and security, 52 terms deep. Each entry is a self-contained, citable definition cross-linked to the related terms and the guide that explains it in depth, with a stable canonical URL so answer engines can quote it.
Identity
- ABAC
Attribute-Based Access Control
ABAC (Attribute-Based Access Control) decides access by evaluating policies over attributes of the user, resource, action, and environment, expressing fine-grained contextual rules that roles alone cannot.
- CIEM
Cloud Infrastructure Entitlement Management
CIEM is a class of tools that scans cloud IAM permissions against actual usage logs to find and right-size over-provisioned entitlements before an attacker can exploit them.
- FIDO2
FIDO2 / WebAuthn
FIDO2 is the FIDO Alliance's open-standard set for phishing-resistant, passwordless authentication with public-key cryptography, comprising the WebAuthn browser API and the CTAP authenticator protocol.
- IGA
Identity Governance and Administration
IGA is the governance layer that certifies, reviews, and audits who has access to what across every application in a company, sitting on top of the provisioning connectors that create and remove the underlying accounts.
- ITDR
Identity Threat Detection and Response
ITDR is security tooling that monitors identity infrastructure, such as Active Directory and IdP login activity, for attack techniques like Kerberoasting and golden ticket forgery that authentication logs alone don't catch.
- JIT Provisioning
Just-in-Time Provisioning
JIT provisioning creates or updates a user's account automatically at the moment they first log in via SSO, reading name, email, and group claims from the SAML assertion or OIDC token instead of requiring an admin to pre-create the account.
- JWT
JSON Web Token
A JWT (JSON Web Token, RFC 7519) is a compact, URL-safe token of signed JSON claims that a recipient can verify without a database lookup; OIDC ID tokens are JWTs.
- Magic Link
A magic link is a single-use, time-limited login token emailed to a user, which authenticates them by redeeming the token for a session on click, eliminating passwords but making the email inbox the entire authentication boundary.
- MFA
Multi-Factor Authentication · 2FA · Two-Factor Authentication
MFA (Multi-Factor Authentication) requires two or more independent factors (something you know, have, or are) to prove identity, so a stolen password alone cannot log an attacker in.
- OAuth 2.0
OAuth · OAuth2
OAuth 2.0 is a delegated authorization framework (RFC 6749) that lets a user grant an app scoped, time-limited access to their data on another service without sharing a password; it is authorization, not authentication.
- OIDC
OpenID Connect
OIDC (OpenID Connect) is a thin authentication layer built on OAuth 2.0 that adds an ID token, a signed JWT the client reads to verify who the user is; it powers most modern consumer login.
- PAM
Privileged Access Management
PAM vaults high-risk credentials like root, domain admin, and cloud IAM admin roles, rotating them automatically and brokering time-boxed, recorded sessions instead of handing standing passwords directly to engineers.
- Passkey
Passkeys
A passkey is a discoverable WebAuthn credential, usually synced across a user's devices, that replaces a password with a phishing-resistant key pair held by the platform.
- PBAC
Policy-Based Access Control · Policy-as-code
PBAC (Policy-Based Access Control) moves the authorization decision into an external policy engine expressed as code (such as OPA/Rego or AWS Cedar), and in practice can express RBAC, ABAC, and ReBAC rules.
- RBAC
Role-Based Access Control
RBAC (Role-Based Access Control) grants permissions to roles and assigns roles to users, so access is decided by the role a user holds; it is the most widely deployed authorization model.
- ReBAC
Relationship-Based Access Control · Zanzibar
ReBAC (Relationship-Based Access Control) decides access by traversing relationships in a graph, the model popularized by Google Zanzibar and used for sharing, hierarchy, and nested ownership.
- Refresh Token
A refresh token is a long-lived credential issued alongside a short-lived OAuth 2.0 or OIDC access token, redeemable only at the authorization server's token endpoint to obtain a new access token without re-authenticating the user.
- SAML
Security Assertion Markup Language · SAML 2.0
SAML (Security Assertion Markup Language) is an XML-based standard for exchanging signed authentication and authorization data between an identity provider and a service provider, and it is the incumbent protocol for enterprise single sign-on.
- SCIM
System for Cross-domain Identity Management
SCIM (System for Cross-domain Identity Management) is a REST API standard for automating user provisioning and deprovisioning between an identity provider and an application, keeping the account lifecycle in sync.
- Session Management
Session management is the set of tokens, timeouts, and revocation controls that keep a user authenticated across requests after login without requiring credentials on every page.
- Token Binding
Token Binding (RFC 8471) was a TLS-layer standard that cryptographically bound a token to its connection so it couldn't be replayed elsewhere; both major browsers dropped support by 2020, and DPoP now delivers the same sender-constrained-token goal at the application layer.
- WebAuthn
Web Authentication API
WebAuthn (Web Authentication) is the W3C browser API for registering and authenticating users with public-key credentials, binding every signature to the page origin to make login phishing-resistant.
AI
- Agentic AI
AI agents
Agentic AI describes systems where a language model plans and acts, calling tools and looping until a task is done; its autonomy multiplies both value and security risk.
- Context window
Token limit
The context window is the maximum amount of text, in tokens, a language model can consider at once, spanning the prompt, history, retrieved documents, and the response.
- Embeddings
Vector embeddings
An embedding is a numeric vector that represents the meaning of text (or an image or audio) so that similar meanings sit close together, enabling search by meaning rather than exact keywords.
- Fine-tuning
LoRA · Model fine-tuning
Fine-tuning adapts a pretrained model to a specific task or style by continuing training on a smaller curated dataset, updating the model's weights; it teaches behavior, not fresh facts.
- Guardrails (LLM)
LLM guardrails
Guardrails are the input, output, and system-prompt controls placed around a language model to constrain what it can receive, say, or do; each layer is porous, so they are defense-in-depth, not a fix.
- Inference
Model inference
Inference is running a trained model to produce an output; it is the recurring, per-request cost of an AI product and the runtime surface attackers hit.
- Jailbreak (LLM)
LLM jailbreak
A jailbreak is a prompt crafted to make a language model ignore its safety training and produce content it was tuned to refuse; it targets model alignment rather than the application's instructions.
- MCP
Model Context Protocol
MCP (Model Context Protocol) is an open standard for how a language model or agent discovers and calls external tools, data, and prompts; each MCP server it connects to is a security boundary.
- MLSecOps
AI SecOps · ML security operations
MLSecOps is the practice of building security into the whole machine-learning lifecycle (data, model, deployment, and inference) as a continuous discipline, the way DevSecOps does for software.
- Prompt injection
Direct injection · Indirect injection
Prompt injection is an attack where untrusted text hijacks the instructions a language model follows; indirect injection, where hostile instructions live inside data the model reads, is the most dangerous form.
- Quantization
Model quantization
Quantization shrinks a model by storing its weights at lower numeric precision (for example 4-bit or 8-bit), cutting memory and inference cost at some accuracy tradeoff.
- RAG
Retrieval-Augmented Generation
RAG (Retrieval-Augmented Generation) grounds a model's answer in documents retrieved at query time rather than only its training data, reducing hallucination and enabling answers over private or fresh data.
- Tool use (function calling)
Function calling
Tool use (function calling) is the mechanism by which a language model invokes external functions instead of only generating text; it is where a language problem becomes a real-world action.
- Vector database
Vector store
A vector database indexes and searches embeddings by similarity rather than exact match, using approximate nearest-neighbor algorithms; it is the retrieval layer behind semantic search and RAG.
Security
- ASPM
Application Security Posture Management
ASPM aggregates findings from SAST, DAST, SCA, IAST, and secrets scanning into one prioritized risk view correlated against the actual running application, rather than five disconnected tool dashboards.
- CNAPP
Cloud-Native Application Protection Platform
CNAPP (Cloud-Native Application Protection Platform) is a consolidated cloud security category that unifies CSPM, CWPP, CIEM, and IaC scanning into one correlated platform, popularized by vendors like Wiz and Palo Alto Prisma Cloud.
- CSPM
Cloud Security Posture Management
CSPM (Cloud Security Posture Management) continuously scans cloud accounts for misconfigurations, like public storage buckets or open security groups, against benchmarks such as CIS, using read-only, agentless API access.
- DAST
Dynamic Application Security Testing
DAST tests a running application from the outside by sending crafted requests (black-box), catching runtime and configuration flaws that static analysis cannot see; pair it with SAST.
- DSPM
Data Security Posture Management
DSPM is a class of tooling that scans cloud data stores to inventory where sensitive data lives, classify what it contains, and flag exposure paths like public buckets or over-permissioned roles.
- EDR
Endpoint Detection and Response
EDR is security software on endpoints that records activity, detects malicious behavior, and lets responders investigate and contain threats, going beyond signature-based antivirus.
- IAST
Interactive Application Security Testing
IAST instruments a running application during QA or staging testing to confirm, from real request traffic, whether a vulnerability is actually reachable and exploitable, cutting the false positives common to static analysis.
- SASE
Secure Access Service Edge
SASE (Secure Access Service Edge) is a cloud-delivered architecture, coined by Gartner in 2019, that converges SD-WAN networking with security capabilities like ZTNA, SWG, and CASB into a single service.
- SAST
Static Application Security Testing
SAST analyzes an application's source code without running it to find security flaws early (white-box); its counterpart DAST tests the running app from the outside.
- SCA
Software Composition Analysis
SCA scans dependency manifests and lockfiles to inventory every open-source package an application uses, direct and transitive, and flags known CVEs and license risk against vulnerability databases like the NVD.
- SIEM
Security Information and Event Management
A SIEM collects, normalizes, and correlates logs and events across an environment to detect and alert on security activity; it presumes a team to run it, so it is usually premature for early startups.
- SOAR
Security Orchestration, Automation, and Response
SOAR automates and orchestrates the response to security alerts with playbooks, sitting downstream of detection (often a SIEM) to cut response time.
- SSE
Security Service Edge
SSE (Security Service Edge) is the security-only subset of SASE, defined by Gartner in 2021, delivering ZTNA, secure web gateway, CASB, and DLP from the cloud without requiring an SD-WAN replacement.
- XDR
Extended Detection and Response
XDR extends EDR beyond the endpoint, correlating telemetry across endpoints, identity, network, email, and cloud into one detection and response platform.
- Zero trust
Zero Trust Architecture · ZTA
Zero trust is a security model that trusts no user, device, or network location implicitly and verifies every request; it replaces the perimeter with per-request authentication and least privilege.
- ZTNA
Zero Trust Network Access
ZTNA grants a user access to a specific application rather than a whole network, after verifying identity, device, and context on each connection; it is the standard replacement for the VPN.