About AT Protocol

What is AT Protocol?

AT Protocol (Authenticated Transfer Protocol) is the foundation of Bluesky and other social apps likeTangled,Spark, and more. Unlike traditional social platforms that lock your data and identity to a single service, AT Protocol gives you complete control over your digital presence. Think of it as an open standard for social networking, similar to how email works across different providers.

Key Features

• PDS Servers: PDS servers are where your data is stored. They can be run by anyone, and they are very lightweight, allowing you to choose which one to use or run your own. PDS servers just store your data, meaning you don't have to switch PDS servers to use a different app or service. You can have one PDS while using many different apps and services with the same account.
• Decentralized Identity: Your account is tied to a DID (Decentralized Identifier) rather than your handle/username. This means you can move your entire account, including your followers and content, to any PDS by changing where your DID points. It's also the reason you can use any domain as your handle, because your identity is not tied to your handle. Your handle can change, but your DID will always remain the same.
• Portable Content: All your posts, likes, and other social data are stored in your Personal Data Server (PDS). You can switch PDS providers without losing any content or connections.
• Architecture: The protocol uses a three-tier architecture: Personal Data Servers (PDS) store your content, relays broadcast a stream of all events on all PDSes, and AppViews process and serve that stream into content for users. This means when you make a post, the content is stored on your PDS, picked up by relays, and AppViews listen to those relays to deliver that post to all users.
• Algorithmic Choice: You're not locked into a single algorithm for your feed. Different services can offer different ways of curating content, and you can choose which one you prefer. Bluesky offers a way to make custom feeds, but even if it didn't, different apps could still offer their own algorithms for curating content.

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