# Federation Architecture [Federation Architecture Overview - Bluesky](https://blueskyweb.xyz/blog/5-5-2023-federation-architecture) ![[federation-architecture-diagram.png]] - Personal Data Server (PDS) - A PDS acts as the participant’s agent in the network. This is what hosts your data (like the posts you’ve created) in your [repo](https://atproto.com/guides/data-repos). It also handles your account & login, manages your repo’s [signing key](https://atproto.com/guides/overview#account-portability), stores any of your private data (like which accounts you have muted), and handles the services you talk to for any request. - Big Graph Service (BGS) - The BGS handles "big-world" networking. It crawls the network, gathering as much data as it can, and outputs it in one big stream for other services to use. It’s analogous to a firehose provider or a super-powered relay node. - App Views - An App View is the piece that actually assembles your feed and all the other data you see in the app, and is generally expected to be downstream from a BGS’s firehose of data. This is a highly semantically-aware service that produces aggregations across the network and views over some subset of the network. This is analogous to a prism that takes in the BGS’ raw firehose of data from the network, and outputs views that enable an app to show a curated feed to a user. For example, the BGS might crawl to grab data such as a certain post’s likes and reposts, and the app view will output the count of those metrics.