AuthZEN is an authorization standard from the OpenID Foundation that defines a common, vendor-neutral way for Policy Enforcement Points (PEPs) to request authorization decisions from Policy Decision Points (PDPs). It enables interoperable, real-time, policy-based access control across applications, APIs, and services, supporting consistent authorization in distributed and cloud-native environments.

Abbreviated Language for Authorization (ALFA) is a high-level, human-readable language for defining access control policies. It simplifies the creation and management of authorization rules by offering a more concise and intuitive syntax, compiling it into XACML, and helping you write, read, and maintain complex policy logic more easily.

eXtensible Access Control Markup Language (XACML) is an OASIS standard for attribute-based access control (ABAC). It provides a policy language and evaluation framework for defining fine-grained authorization rules based on attributes such as user, resource, action, and environment, enabling dynamic and context-aware access decisions across systems.

A policy enforcement point (PEP) enforces access in places such as an application, API, or gateway. A policy decision point (PDP) evaluates authorization policies and decides whether to allow or deny access.

Standards reduce fragmentation by ensuring different systems can communicate in a consistent way. This improves interoperability, reduces custom integration work, strengthens security consistency, and helps organizations scale authorization across complex environments.

At their best, standards:

• Enable interoperability across vendors and platforms
• Reduce complexity for developers and enterprises
• Improve security, governance, and compliance