The USP (User Services Platform) permission system is a critical component of the TR-369 specification, designed to provide robust and granular access control for managing connected devices. It's a complex interplay between the Controller and the Agent, leveraging various mechanisms to ensure security and compliance.
The USP permission system operates on the principle of least privilege, meaning that any entity (Controller) interacting with a USP Agent (the managed device) should only be granted the minimum necessary access rights to perform its intended function. This is vital in heterogeneous environments with multiple stakeholders (e.g., ISPs, IoT platforms, end-users) and diverse devices.
The system is characterized by a layered approach:
- Controller-Side (Proactive Evaluation): The Controller is responsible for determining if its internal user (human or automated process) is authorized to initiate a specific USP operation. This acts as a first lin