AuthZ vs AuthN are two distinct concepts that are often conflated due to their similar names. Authentication (authN) is who you are, while authorization (authZ) is what you're allowed to do. The problem with attribute-based permission systems is that they struggle with interpreting and applying significance to the presence of attributes, leading to security vulnerabilities. Relationship-Based Access Control (ReBAC) offers a modern approach by focusing on the relationships between users or services and resources, rather than traditional role-based access control or attribute-based access control. ReBAC allows for fine-grained access control, intuitive management, and a collaborative approach, promoting a more robust permission system that can withstand changes to the organization.