The following is a message encrypted using multiplicative cipher but you do not know the key. Decrypt the message and show all your work. VNY LYQ EHH VNY TSD DYL YRO YSR VNY KWL HTJ YVK YYR NEF SRI QWM YVN SRI VWQ EUE RTN EFS RIV WQE UQW MYV NSR I

2. Encrypt the word SHIELD using an alphabetic Caesar shift cipher that starts with a shift of 8 (A to I) and shifts one additional space after each character is encrypted. Original A BC|DE F GHI J KLMN 0PQR STUV WXY Z Maps to I J KLMNOPQRS TUVW XYZ ABCDE FGH Write the encrypted message for the word SHIELD:

Encrypt the message " HALT " by translating the letters into numbers(via A=0,B=1,C=2,D=3,E=4,F=5,G=6,H=7,I=8,A=0,B=1,C=2,D=3,E=4,F=5,G=6,H=7,I=8,J=9,K=10,L=11,M=12,N=13,O=14,P=15,Q=16,R=17,J=9,K=10,L=11,M=12,N=13,O=14,P=15,Q=16,R=17,S=18,T=19,U=20,V=21,W=22,X=23,Y=24,Z=25S=18,T=19,U=20,V=21,W=22,X=23,Y=24,Z=25 )and then applying the encryption function given, and then translating the numbers back into letters.(a) f(p)=(p+4) mod 26 _____ (b) f(p)=(p+10) mod 26 ____ (c) f(p)=(p+7) mod 26 _____

Use C language

One of the one-way functions used in public key cryptography is integer multiplication/factorization. Multiplying two integers is easy, but factoring is hard. The number 1765243 is the product of two primes. What is the smaller of the two primes? What is the largest of the two primes?

message "masterpiece" key = 1939 digitalCipher (message, key) m a S ter p i e 13 1 19 20 5 18 16 9 5 3 +19 3 9 1939 19 --- = Examples [14, 10, 22, 29, 6, digitalCipher("scout", 1939) с e in m 5 14 10 22 29 6 27 19 18 6 12 8 3 [20, 12, 18, 30, 2:

Use Pyhton

This problem uses a real-world example of a symmetric cipher, from an old U.S. Special Forces manual (public domain). The document, filename Special Forces.pdf, is available at box.com/CompSec4e. b. i. Using the two keys (memory words) cryptographic and network security, encrypt the following message: Be at the third pillar from the left outside the lyceum theatre tonight at seven. If you are distrustful bring two friends. Make reasonable assumptions about how to treat redundant letters and excess letters in the memory words and how to treat spaces and punctuation. Indicate what your assumptions are. Note: The message is from the Sherlock Holmes novel The Sign of Four. ii. Decrypt the ciphertext. Show your work. iii. Comment on when it would be appropriate to use this technique and what its advantages are.

The ciphertext "einnd tdkng" is obtained using the substitution cipher with the key below. What is the plaintext? plain alphabet : abc de f g hijkl m nopqrstu v w x y cipher alphabet: p hq g i u me a yln o fd x jkrcv st z w b е а

Cryptography Question: