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# PDFEncryptionAlgorithmEnum

PDFEncryptionAlgorithmEnum enumeration constants are used to specify the encryption algorithm for exported PDF files.

```
typedef enum {
  PDFEA_RC4
  PDFEA_AES128
  PDFEA_AES256
} PDFEncryptionAlgorithmEnum;
```

## Elements

| Name            | Description                                                                                                                                                                                                                                                                                      |
| --------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| PDFEA\\\_RC4    | RC4 encryption supported for PDF version 1.3 (40-bit key only) and PDF version 1.4 or above (longer keys up to 128 bit). Key length is set using the [PDFEncryptionInfo::KeyLength](/fine-reader/engine/api-reference/parameter-objects/export-parameters/pdfencryptioninfo#keylength) property. |
| PDFEA\\\_AES128 | 128-bit AES encryption supported for PDF version 1.6 and above.                                                                                                                                                                                                                                  |
| PDFEA\\\_AES256 | 256-bit AES encryption supported for PDF version 1.7 and above.                                                                                                                                                                                                                                  |

## Used in

[PDFEncryptionInfo::EncryptionAlgorithm](/fine-reader/engine/api-reference/parameter-objects/export-parameters/pdfencryptioninfo#encryptionalgorithm)