1# Protecting Asset Data with User Authentication
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3> **NOTE**
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5> The asset data mentioned in this topic refers to sensitive data less than 1024 bytes in size, including passwords, app tokens, and other critical data (such as bank card numbers).
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7## When to Use
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9Asset store service (ASSET) can be used in the scenario, in which users need to view their bank card numbers using a financial/banking application. To ensure security, you can store bank card numbers in an asset store and enforce a user identity authentication before the back card number is accessed.
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11When a user wants to view the bank card number, the application requests an identity authentication (for example, the user needs to enter a lock screen password or pass certain biometric authentication). When the identity authentication is successful, the application obtains the bank card number from ASSET and presents it to the user.
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13## Development Process
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15The following figure illustrates the development process.
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17> **NOTE**
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19> UserIAM provides only ArkTS APIs. Therefore, only ArkTS APIs can be used.
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21![](figures/flowchat-auth-required.png)
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231. The service queries an asset and determines whether the asset exists in the asset store based on the query result.
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25   For details about the development procedure, see [Querying Assets](asset-js-query.md). For details about the sample code, see [Querying Attributes of an Asset](asset-js-query.md#querying-attributes-of-an-asset).
262. If the asset does not exist, add an asset. For details, see [Adding an Asset](asset-js-add.md).
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283. If the asset exists, the service can perform any of the following operations based on service requirements:
29    * Remove the asset. For details, see [Removing Assets](asset-js-remove.md).
30    * Update the asset. For details, see [Updating an Asset](asset-js-update.md).
31    * Query the plaintext of the asset. The query process involves preprocessing, user authentication, plaintext query, and postprocessing. For details, see [Querying an Asset with User Authentication](asset-js-query-auth.md).
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