exsre

Exsre, short for Extended Secure Resource Exchange, is a term used in some discussions to describe a proposed framework for secure cross-domain resource sharing in distributed systems. It is not an officially ratified standard, and definitions vary. In its broadest sense, exsre envisions a protocol stack that combines strong policy-based access control, auditable token exchange, and interoperable resource discovery to enable controlled sharing of data and services between tenants or domains.

Conceptually, exsre models three roles: clients, resource servers, and an authorization/policy engine. Access requests are mediated by tokens that carry claims about user identity and resource permissions. A policy engine evaluates dynamic rules at the resource boundary, allowing fine-grained access control and the ability to revoke access in real time. Proponents often describe exsre as designed to work alongside existing standards such as OAuth 2.0, OpenID Connect, and JWT, leveraging these formats for identity, authorization, and token exchange.

Implementation discussions typically address token introspection, revocation, and comprehensive auditing, as well as cross-domain trust management and schema evolution. Performance and interoperability challenges are noted, given the need to coordinate policy evaluation across multiple domains.

Usage and status: Exsre remains largely theoretical or in early-stage prototypes rather than a deployed, recognized standard. It is sometimes referenced in academic or industry discussions as a design reference point when comparing access-control models or as a basis for proof-of-concept experiments.

See also: OAuth 2.0, OpenID Connect, JSON Web Token, access control, policy-based access control.