Notes:
- Pleaseinclude a cover sheet with your lab.
- Write your lab in essay form.
- Look-up each cipher tool and include a short description of each.
- Please answer the following questions and explain how you derived to your answer for each of the lab problems.
- You must include screen-shots to show your work.
1) Caesar Cipher: What does the cipher text below say? Please work this by hand then use the tool at the following link to check your answer. How long did it take you to decipher this message?
LZAK AK S LWKL GX LZW USWKSJ KZAXL UAHZWJ HDWSKW LWDD EW OZSL LZAK EWKKSYW KSQK
2) VigenèreSquare Tool Cipher:Basically, the same as above however this time encipher the message.
The message to encipher is: MEETNINETUESDAYBRINGPROPERMATERIALS
The keyword is: JOEGIORDANOUTICACOLLEGE
Please try to work this by hand.
Use the following web site to help you:
After you have enciphered check your answer by using link below: http://sharkysoft.com/vigenere/1.0/
Why is the Vigenèrecipher stronger than a monoalphabeticcipher?
3) XOR Encryption:I have used XOR encryption to encrypt a word made up of seven characters. The characters of this word have each been encrypted used using XOR encryption. The cipher text of the word is as follows:
00010000
00011011
00010110
00000111
00001100
00000101
00000001
The key is: 01010101
Take each binary digit and XOR it with each binary digit of the key. This will result in a new 8-bit code. This new code corresponds to the plaintext. Use com/xor-encryption.shtml”>http://www.tech-faq.com/xor-encryption.shtmlto guide you through the decryption phase. After you have applied the key to the binary strings above you can use the ASCII to binary conversion chart at com/res/tablesASCII-c.html”>http://www.pcguide.com/res/tablesASCII-c.html to determine what letter each eight bit string stands for and thus what the word is.
4) HomophonicCipher: The Homophonic Substitution Cipher involves replacing each letter with a variety of substitutes, the number of potential substitutes being proportional to the frequency of the letter. For example, the letter ‘a’ accounts for roughly 8% of all letters in English, so we assign 8 symbols to represent it. Each time an ‘a’ appears in the plaintext it is replaced by one of the 8 symbols chosen at random, and so by the end of the encipherment each symbol constitutes roughly 1% of the ciphertext. The letter ‘b’ accounts for 2% of all letters and so we assign 2 symbols to represent it. Each time ‘b’ appears in the plaintext either of the two symbols can be chosen, so each symbol will also constitute roughly 1% of the ciphertext. In the example at the link below, the substitutes happen to be 2-digit numbers, there are between 1 and 12 substitutes for each letter, depending on the letter’s relative abundance.
Given the following encoded message try to figure out what is says.
15 54 57 60 72 42 04 86 33 85 08 97 32 13 92 62 07 26 51 64 25 24
5) Decryption: What does the following quote say? Who said it? Do this by hand. How long did it take you to decipher this message?
DILLCDD RD ETC MZRWREB EY JY OSYF YQC OMRWISC EY MQYETCS XRET QY WYDD YO CQETIDRMDF.
DRS XRQDEYQ LTISLTRWW
6)File Hashing: Please check out the following link for a fun fact related to the United States Cyber Command:
Copy the USCYBERCOM mission statement (below) into the string hash text box:
USCYBERCOM plans, coordinates, integrates, synchronizes and conducts activities to: direct the operations and defense of specified Department of Defense information networks and; prepare to, and when directed, conduct full spectrum military cyberspace operations in order to enable actions in all domains, ensure US/Allied freedom of action in cyberspace and deny the same to our adversaries.
CAREFULLY copy this – because one additional space can change everything! If you have done it correctly, things should check out, but why?


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