# Federated Registries Explained ## What Is a Federated Registry? A federated registry is a network of independently operated directories that synchronise their entries to provide a **unified, globally searchable database** of content and metadata declarations. Rather than relying on a single central authority, multiple registries participate in a **shared protocol**, enabling: * Distributed operation across sectors and jurisdictions * Trust through digital signatures and public key infrastructure * High-availability querying by AI developers, search engines, and compliance tools Each registry publishes **minimal metadata** derived from the original declaration – just enough to confirm the rights status of a piece of content identified by an ISCC code. ## How It Works Registries use a distributed data structure known as a **Distributed Hash Table (DHT)** to store and resolve declarations. Each registry entry is indexed using cryptographic identifiers, including: * An **ISCC code** as a persistent fingerprint of the media asset * A **Declaration (CID)** derived from metadata, hashes, and signer identity * A **Decentralized Identifier (DID)** referencing the declaring party * A **timestamp** with cryptographic signatures for authenticity and traceability * Cryptographic **signatures** that allow to verify the integrity of the full metadata record This system ensures that anyone – whether an online platform, AI developer, or rights organisation – can verify the declared rights associated with a specific work using public registry data. Verification does not require access to full metadata or private storage systems. The declaring party’s identity is referenced through a Decentralized Identifier (DID) and supported by qualified certificates or verifiable credentials, enabling trust without disclosing personal information. ## Operated by Many, Working as One Registries can be run by creator groups, collecting societies, standards bodies, or compliance platforms. Each operator: * Maintains its own node in the registry network * Publishes declarations relevant to its members or mandate * Can mirror or subscribe to declarations from other nodes Because all registries speak the same "language" – a common metadata schema and synchronisation protocol – they function as **parts of a shared infrastructure**, even if operated independently. ## Tailored Access, Public Discovery The registry layer is **public by design**—anyone can query it to check whether a content asset has been declared for a particular use case. At the same time, access to the full declaration data (stored separately) can be governed by access policies, ensuring **flexibility in governance and compliance**. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.tdmai.org/federated-registries/federated-registries-explained.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.