1# Account Management Overview 2 3<!--Kit: Basic Services Kit--> 4<!--Subsystem: Account--> 5<!--Owner: @steven-q--> 6<!--Designer: @JiDong-CS1--> 7<!--Tester: @zhaimengchao--> 8<!--Adviser: @zengyawen--> 9 10## Introduction 11 12The system allows multiple system (OS) accounts to be created on a device. This allows multiple users to use the same device. The data of multiple users is isolated by system account to ensure data security. 13 14## Basic Concepts 15 16Users are identified by accounts. A user can have multiple accounts. The **account** module manages the following types of accounts: 17 18- System account: unique identifier of a user on a device. 19 20- Domain account: unique identifier of a user in a specific domain, such as a company or school. 21 22- Distributed account: identifier of a user on a distributed network. It is provisioned, authenticated, and maintained by an organization or authority and can be used for authentication, networking, and service invocation between devices. 23 24- App account: unique identifier of an app user. Its lifecycle is managed by the application. 25 26## Relationships Between Accounts 27 28 29 30The **account** module uses the system account as the core for account management, in which other types of accounts are related to the system account in one way or another. 31 32- The domain account and the system account are in one-to-one (1:1) relationship, and have the same lifecycle. 33- The distributed account and the system account are in one-to-many (1:N) relationship. A user can bind a distributed account to a system account. Different system accounts can have the same distributed account. The lifecycle of a distributed account is independent of that of a system account. 34- The app account and the system account are in many-to-many (N:M) relationship. A user can have multiple app accounts under different system accounts. Different system accounts can have the same app account. The lifecycle of an app account is independent of that of a system account. 35- There is no direct relationship between the domain account, distributed account, and app account. 36 37When a system account is deleted, the associated domain account, distributed account, and app accounts are also deleted.
