Hello, needing help with Cryptology

1.) Provide a formal definition of the Gen, Enc, and Dec algorithms for the mono-alphabetic. substitution and Vigen ere ciphers. 2.) The ciphertext shown below obtain from the plaintext using a Vigen ere cipher. Show how to decrypt this message. KCCPKBGUFDPHQTYAVINRRTMVGRKDNBVFDETDGILTXRGUD DKOTFMBPVGEGLTGCKQRACQCWDNAWCRXIZAKFTLEWRPTYC QKYVXCHKFTPONCQQRHJVAJUWETMCMSPKQDYHJVDAHCTRL SVSKCGCZQQDZXGSFRLSWCWSJTBHAFSIASPRJAHKJRJUMV GKMITZHFPDISPZLVLGWTFPLKKEBDPGCEBSHCTJRWXBAFS FFSQESVYCLACNVRWBBIREPBBVFEXOSCDYGZWPFDTKFQIY CWHJVLNHIQIBTKHJVNPIST Figure 1.1. Ciphertext obtained using a Vigen ere cipherl 3.) For each of the following encryption schemes, state whether the scheme is perfectly secret. Justify your answer in each case (a) The message space is M = {0, . . . , 4) Algorithm Gen chooses a uniform key from the key space {0, 5). Enck(m) returns [km mod 5, and Deck(c) returns [c - k mod 5]. (b) The message space is Mm [0, 1) the last bit of m is 0). Gen chooses a uniform key from (o, 1}.-1. Enck(m) returns ciphertext m (kko), and Deck(c) returns c (kko). 1.) Provide a formal definition of the Gen, Enc, and Dec algorithms for the mono-alphabetic. substitution and Vigen ere ciphers. 2.) The ciphertext shown below obtain from the plaintext using a Vigen ere cipher. Show how to decrypt this message. KCCPKBGUFDPHQTYAVINRRTMVGRKDNBVFDETDGILTXRGUD DKOTFMBPVGEGLTGCKQRACQCWDNAWCRXIZAKFTLEWRPTYC QKYVXCHKFTPONCQQRHJVAJUWETMCMSPKQDYHJVDAHCTRL SVSKCGCZQQDZXGSFRLSWCWSJTBHAFSIASPRJAHKJRJUMV GKMITZHFPDISPZLVLGWTFPLKKEBDPGCEBSHCTJRWXBAFS FFSQESVYCLACNVRWBBIREPBBVFEXOSCDYGZWPFDTKFQIY CWHJVLNHIQIBTKHJVNPIST Figure 1.1. Ciphertext obtained using a Vigen ere cipherl 3.) For each of the following encryption schemes, state whether the scheme is perfectly secret. Justify your answer in each case (a) The message space is M = {0, . . . , 4) Algorithm Gen chooses a uniform key from the key space {0, 5). Enck(m) returns [km mod 5, and Deck(c) returns [c - k mod 5]. (b) The message space is Mm [0, 1) the last bit of m is 0). Gen chooses a uniform key from (o, 1}.-1. Enck(m) returns ciphertext m (kko), and Deck(c) returns c (kko)