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Cryptography

Question
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Please solve this for me.
The following enciphered message was intercepted. Derive the type of algorithm used, then recover the key, decrypt the message and answer the question
FHHJJFSIVQQMKMBCBZXCQMKMXU
4) Alice and Bob are going to use a Vigenere cipher with the bit stream generated by a 4 bit linear shift register:
b<sup>,</sup><sub>1 </sub>< --b<sub>2</sub>
b<sup>,</sup><sub>2 </sub><<sub> </sub>--b<sub>3 </sub>
b<sup>,</sup><sub>3 </sub><-- b<sub>4</sub>
b<sup>,</sup><sub>4 </sub><-- b<sub>2</sub>+b<sub>4</sub>
<sub> </sub>
String w/
b<sup>,</sup><sub>1 </sub>= 1
b<sup>,</sup><sub>2 </sub>= 0
b<sup>,</sup><sub>3 </sub> = 0
b<sup>,</sup><sub>4 </sub>= 1
Populate the frequency table and decipher the following message in binary
Form):
01110010 10011000 11110010 10001010
Sunday, December 9, 2018 6:40 PM
Answers
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The only forum I can find that deals with cryptography is here:
https://social.msdn.microsoft.com/Forums/en-us/home?forum=AzureDiskEncryption
Links to Vigenere cipher decoders here:
But I would expect a frequency analysis of such a short message to not be useful.
Richard Mueller - MVP Enterprise Mobility (Identity and Access)
- Proposed as answer by Dave PatrickMVP Sunday, December 9, 2018 7:23 PM
- Marked as answer by Dave PatrickMVP Sunday, December 16, 2018 2:32 PM
Sunday, December 9, 2018 7:11 PM -
Depending on the context might also try over here.
https://social.technet.microsoft.com/Forums/en-US/home?forum=win10itprosecurity
https://social.technet.microsoft.com/Forums/en-US/home?forum=w8itprosecurity
https://social.technet.microsoft.com/Forums/en-US/home?forum=w7itprosecurity
https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?category=vslanguages
Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows Server] Datacenter Management
Disclaimer: This posting is provided "AS IS" with no warranties or guarantees, and confers no rights.- Proposed as answer by Richard MuellerMVP Monday, December 10, 2018 2:57 AM
- Marked as answer by Dave PatrickMVP Sunday, December 16, 2018 2:32 PM
Sunday, December 9, 2018 7:25 PM
All replies
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The only forum I can find that deals with cryptography is here:
https://social.msdn.microsoft.com/Forums/en-us/home?forum=AzureDiskEncryption
Links to Vigenere cipher decoders here:
But I would expect a frequency analysis of such a short message to not be useful.
Richard Mueller - MVP Enterprise Mobility (Identity and Access)
- Proposed as answer by Dave PatrickMVP Sunday, December 9, 2018 7:23 PM
- Marked as answer by Dave PatrickMVP Sunday, December 16, 2018 2:32 PM
Sunday, December 9, 2018 7:11 PM -
Depending on the context might also try over here.
https://social.technet.microsoft.com/Forums/en-US/home?forum=win10itprosecurity
https://social.technet.microsoft.com/Forums/en-US/home?forum=w8itprosecurity
https://social.technet.microsoft.com/Forums/en-US/home?forum=w7itprosecurity
https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?category=vslanguages
Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows Server] Datacenter Management
Disclaimer: This posting is provided "AS IS" with no warranties or guarantees, and confers no rights.- Proposed as answer by Richard MuellerMVP Monday, December 10, 2018 2:57 AM
- Marked as answer by Dave PatrickMVP Sunday, December 16, 2018 2:32 PM
Sunday, December 9, 2018 7:25 PM