Computer Sciences and Information Technology - Assignment Example

The encrypted message is not visible in plain sight but can be retrieved with the use of the same application, thus it becomes very easy to hide confidential data.
The process of encryption and decryption of message into an image is demonstrated in the following steps:
1. A new folder is created onto the desktop and named Peek-A-Boo.
2. All files of the S-Tool application are copied into this folder.
3. Now, the image file named ‘marbles.bmp’ file is downloaded in the Peek-A-Boo folder. This image should be used for demonstration purposes.
4. A .txt file is created with the notepad. It contains only one sentence stating “Don’t forget your lunch.” and then renamed as message.txt and saved into the Peek-A-Boo folder.
5. Next, from the Peek-A-Boo folder the S-Tool.exe file is opened by double-clicking on it.
6. The S-Tool dialog box appears as below:
7. At first the marble.bmp image file is dragged into the S-Tool window.

8. Then the.txt file is dragged over the image file into the S-Tool application. A dialog box appears on the screen asking for a passphrase, which will be used for both hiding and retrieving the information.

9. The passphrase used for this encryption process is given as ‘pass’ and the Encryption Algorithm is set to ‘IDEA’ from the drop-down box.

10. Within a few seconds after pressing ok, a new window entitled ‘hidden data’ opens up with the image. This image contains the .txt file within itself but cannot be differentiated in plain sight.

11. Right-click on the hidden data image and select the ‘save as’ option to select a destination folder. The hidden data image is then saved as ‘hidden-message.bmp’ into the Peek-A-Boo folder.
12. Then all the S-Tool applications and Peek-A-Boo folder are closed. The information is stored in the hidden-message image file.
13. Now, pretending as our own conspirators, we will try to retrieve the information from the image file.
14. The S-Tool application is again opened from the Peek-A-Boo folder and the hidden-message image file is dragged into it. This is how it shows:


15. Right-click on the image > Select ‘Reveal’. Again the dialog appears requesting to give the passphrase used for encryption.

16. The passphrase ‘pass’ is given the same as before and press ok.

17. A small window appears on the screen specifying the text file that is hidden in the image.
19. By double-clicking on the “message-revealed.txt’ file, the message can be viewed which is exactly the same as the original one.
Part B
Soylent Green –the case of Computer Forensic Mystery
Solomon Roth needs to use the S-Tool to decrypt the information about the murder mystery of New York Soylent's board member William R. Simonson. The information is saved in the image files of Thorn’s computer files but the passphrase is not yet found. The passphrase can be recovered from http://www.fourmilab.ch/javascrypt/javascrypt.html by using the ciphertext and the encryption key. The process is given below:

1. Open the link http://www.fourmilab.ch/javascrypt/javascrypt.html
2. Select the option Encryption/decryption utility from the javaScript components provided on the page. The new page appears as below.
3. The Ciphertext along with the key to be provided in the respective space to retrieve the passphrase and press ‘decrypt’. The passphrase Thorn’ appears on the plain text
4. Thus Sol receives the passphrase to decrypt the message from the images using S-Tool.
The next step is to retrieve the information from the three image files about the murder.
The process is shown in the following steps:

1. Again the S-Tool application is opened.
2. The first image file from the PEEKABOO Evidence folder is dragged into the S-Tool application window.
3. Right-click on the image > select ‘Reveal’. The dialog box appears on the screen asking for a passphrase.
4. The passphrase ‘Thorn’ is provided and then ’ok’. A small window appears which mentioned that a .wav file is encrypted in the image.5. The .wav file is then saved in the PEEKABOO folder.
6. When this file is opened, it said “You got to tell then Soylent Green’s people”.
Other images files are clean and do not hold any information within themselves. Thus it is found that the people of Soylent Green are responsible for William R. Simonson’s murder.