File encryption of Cryptography experiment

File encryption and decryption experiment

[content of the experiment]

Use DES, AES and RC2 algorithms to encrypt and decrypt text, picture, audio, video and other files.

File encryption and decryption experiment

[experimental principle]

Some private or confidential files in computers that are not suitable for public disclosure can be easily stolen and illegally exploited. The fundamental way to solve this problem is to encrypt important files. In practical applications, most of them directly use the system's own tools or other special tools for file encryption and decryption tools all use a variety of encryption and decryption algorithms to protect files.

In this experiment, the contents of text, picture, audio, video and other files are encrypted and decrypted by DES, AES and RC4 algorithms. The general process of encryption is to read the contents of the file, encrypt, write the ciphertext to the file for content coverage, and save the decryption process is similar.

File encryption and decryption experiment

[experimental environment]

ISES client

[experimental steps]

Here, take text files as an example. Other files such as pictures, audio and video can be referenced.

(1) the plaintext content of the new file is shown in figure 1.1.91.

Figure 1.1.91

(2) use DES algorithm to encrypt the file as shown in figure 1.1.92.

Figure 1.1.92

(3) check that the encrypted file as shown in figure 1.1.93 has been encrypted by DES algorithm.

Figure 1.1.93

(4) decrypt the encrypted file as shown in figure 1.1.94 to view the decrypted file and compare it with the file before encryption as shown in figure 1.1.95.

Figure 1.1.94

Figure 1.1.95

(5) modifying the key to decrypt the file will indicate that the decryption failed as shown in figure 1.1.96.

Figure 1.1.96

(6) choose AES and RC2 algorithms to encrypt and decrypt the file and compare the encryption and decryption results.