# Application Authorization

Every request to the **Private User API must have an application authorization header** which provides the application's API-Keys.

**This authentication layer ensures only preapproved applications can access this API.**

The application must also relay customer information to the API such as IP address and User-Agent for security reasons and to ensure actions such as rate-limiting and bruteforce blocks are effective.

**Required Headers for all requests&#x20;**<mark style="color:red;">**(Values are examples and are not real)**</mark>**:**

| NAME                                      | VALUE                                                                                                                                             |
| ----------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- |
| X-Application-API-Private-Key             | e3bf910e41d2cec9b7813ec6973016bde756a6543294ff1f6800f8de629c8                                                                                     |
| X-Application-API-Public-Key              | 73016bde756a6543294ff1f6800f8de629c8e3bf910e41d2cec9b7813ec69                                                                                     |
| X-Application-Forwarded-Client-IP-Address | 193.0.0.0                                                                                                                                         |
| X-Application-Forwarded-Client-User-Agent | Google Chrome on Windows 10 - "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.82 Safari/537.36 |


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