Mozilla accounts server (former FxA) and Firefox Sync Server (syncserver)

Mozilla Accounts Server (fxa-auth-server):

  • Manages user authentication (sign-up, login, password reset, etc.).
  • Issues authentication tokens that allow users to access various Mozilla services, including Firefox Sync.

Users to authenticate through this server before syncing their data.

Mozilla accounts offers an end-to-end encryption support feature for OAuth reliers by deriving a strong encryption key from user’s password.

Firefox Sync Server (syncserver):

  • Stores and syncs browser data (bookmarks, passwords, history, etc.).
  • Requires authentication via the Mozilla Accounts Server before allowing access to synced data.
  • Does not handle user accounts directly but relies on authentication tokens from the Mozilla Accounts Server.

How They Work Together:

  • When a user logs into Firefox Sync, their credentials are verified by the Mozilla Accounts Server.
  • Upon successful authentication, the Mozilla Accounts Server provides an OAuth token to the client (Firefox).
  • The Firefox client then uses this token to authenticate with the Firefox Sync Server, which allows it to store and retrieve synced data.

https://mozilla-services.readthedocs.io/en/latest/howtos/run-fxa.html

There is some confusion, since Mozilla Sync Storage (Syncstorage-rs written in Rust) also exists, which might (?) eventually replace syncserver.