2.2 (A good substitution cipher). Consider a variant of the substitution cipher & = (E, D)...

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2.2 (A good substitution cipher). Consider a variant of the substitution cipher & = (E, D) defined in Example 2.3 where every symbol of the message is encrypted using an independent permutation. That is, let M = C = L for some a finite alphabet of symbols and some L. Let the key space be K = SL where S is the set of all permutations on . The encryption algorithm E(k, m) is defined as E(k, m): (k[0] (m[0]), k[1](m[1]), . Show that is perfectly secure. k[L 1](m[L 1]) ) 2.2 (A good substitution cipher). Consider a variant of the substitution cipher & = (E, D) defined in Example 2.3 where every symbol of the message is encrypted using an independent permutation. That is, let M = C = L for some a finite alphabet of symbols and some L. Let the key space be K = SL where S is the set of all permutations on . The encryption algorithm E(k, m) is defined as E(k, m): (k[0] (m[0]), k[1](m[1]), . Show that is perfectly secure. k[L 1](m[L 1]) )