isX

isX is a specification and software ecosystem for standardized, interoperable exchange of identity-related data and service requests across organizational boundaries. It defines a common data model for identity attributes, a messaging protocol, and a trust framework to support authentication, authorization, and attribute sharing between identity providers and service providers.

It aims to enable interoperable identity workflows while preserving user privacy and consent. The core components include a modular data schema for attributes, a request-response protocol, and reference implementations. isX supports privacy-preserving features such as data minimization, user consent capture, and auditable attribute provenance.

Architecturally, isX envisions a three-party model consisting of identity providers, relying parties (service providers), and user agents. Communications are secured with transport-layer security, digital signatures, and optional decentralized trust mechanisms. The standard emphasizes interoperability with existing protocols such as OAuth 2.0, OpenID Connect, SAML, and SCIM where applicable.

Development of isX has been community-driven, organized by a standards body with public drafts and working groups. Governance typically includes versioned releases, reference conformance tests, and ecosystem tooling to promote compatibility across vendors and deployments.

Adoption patterns vary by sector but commonly include enterprise identity federations and government or healthcare contexts where controlled attribute sharing is needed. Implementations range from full identity federation stacks to lightweight connectors that bridge legacy systems with modern identity platforms.

Critiques focus on privacy risk, complexity of integration, and the need for robust consent and data governance. Successful deployment often requires governance agreements, data mappings, and ongoing audits to ensure compliance with applicable data protection laws.