Identity Provider (IdP) & SSO

An Identity Provider (IdP) is a system that creates, stores and verifies digital identities and issues authentication assertions (for example SAML, OAuth 2.0 / OpenID Connect tokens) to relying parties. Single Sign‑On (SSO) is the user experience and workflow enabled by an IdP that lets an authenticated user access multiple applications without re-entering credentials, widely used across enterprise, cloud and government applications worldwide.

Think of an IdP + SSO like a club bouncer and a wristband: the IdP checks your identity, vouches for you, and hands out a token so you can move between rooms without a repeat ID check. When you sign in, the IdP performs authentication (password, MFA, certificate), issues an assertion or token using protocols such as SAML or OpenID Connect, and redirects or provides that token to the service provider. The service validates the token, establishes a session, and grants access based on the asserted identity and attributes. You’ll find this flow across SaaS apps, enterprise portals and federated services because it centralizes access control, simplifies user experience and streamlines auditing.

The market is led by cloud identity providers and hyperscalers, with on‑prem IAM suites and open‑source projects serving heavily regulated or bespoke deployments. Primary buyers are enterprises, SaaS vendors, public sector bodies and managed service providers that need centralized authentication, SSO and compliance capabilities. Suppliers range from pure‑play IdP vendors and platform providers (enterprise SaaS and hyperscalers) to system integrators and security vendors that bundle identity with access management and PAM. Standards bodies, privacy regulations (GDPR, CCPA) and regional compliance requirements drive procurement choices, and integrators/MSPs often influence implementation and regional adoption patterns.