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3.1.2.3. Proses Dekripsi
Proses dekripsi merupakan kebalikan dari proses enkripsi. Proses dekripsi menggunakan algoritma yang sama dengan proses enkripsi. Sebagai contoh, misalkan
ingin didekripsikan kembali hasil enkripsi yang telah didapatkan di atas, maka proses dekripsinya adalah sebagai berikut :
PROSES DEKRIPSI PUTARAN - 1
01 L1 = X1 K1 mod 216 + 1 = 1100101101010100 0010001000010011 mod 216 + 1 = 0010010000101100
02 L2 = X2 + K2 mod 216 = 0101001000101100 + 1011001111110100 mod 216 = 0000011000100000
03 L3 = X3 + K3 mod 216 = 1110100000101001 + 1011001110110100 mod 216 = 1001101111011101
04 L4 = X4 K4 mod 216 + 1 = 0100001001110010 0111011110010011 mod 216 + 1 = 0000011001101101
05 L5 = L1 XOR L3 = 0010010000101100 XOR 1001101111011101 = 1011111111110001
06 L6 = L2 XOR L4 = 0000011000100000 XOR 0000011001101101 = 0000000001001101
07 L7 = L5 K5 mod 216 + 1 = 1011111111110001 0010011000100110 mod 216 + 1 = 0010011100101100
08 L8 = L6 + L7 mod 216 = 0000000001001101 + 0010011100101100 mod 216 = 0010011101111001
09 L9 = L8 K6 mod 216 + 1 = 0010011101111001 0010011000000110 mod 216 + 1 = 1101110011111010
10 L10 = L7 + L9 mod 216 = 0010011100101100 + 1101110011111010 mod 216 = 0000010000100110
11 L11 = L1 XOR L9 = 0010010000101100 XOR 1101110011111010 = 1111100011010110
12 L12 = L3 XOR L9 = 1001101111011101 XOR 1101110011111010 = 0100011100100111
13 L13 = L2 XOR L10 = 0000011000100000 XOR 0000010000100110 = 0000001000000110
14 L14 = L4 XOR L10 = 0000011001101101 XOR 0000010000100110 = 0000001001001011
Untuk putaran berikutnya : X1 = L11 = 1111100011010110
X2 = L12 = 0100011100100111
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X3 = L13 = 0000001000000110 X4 = L14 = 0000001001001011
PUTARAN - 2 01 L1 = X1 K1 mod 216 + 1 = 1111100011010110
1110111100100110 mod 216 + 1 = 1101000101010001 02 L2 = X2 + K2 mod 216 = 0100011100100111 + 1101100111011010
mod 216 = 0010000100000001 03 L3 = X3 + K3 mod 216 = 0000001000000110 + 1111100111011010
mod 216 = 1111101111100000 04 L4 = X4 K4 mod 216 + 1 = 0000001001001011
0101011110000000 mod 216 + 1 = 1010000110111000 05 L5 = L1 XOR L3 = 1101000101010001 XOR 1111101111100000 =
0010101010110001 06 L6 = L2 XOR L4 = 0010000100000001 XOR 1010000110111000 =
1000000010111001 07 L7 = L5 K5 mod 216 + 1 = 0010101010110001
0000011000100110 mod 216 + 1 = 0111101101000000 08 L8 = L6 + L7 mod 216 = 1000000010111001 +
0111101101000000 mod 216 = 1111101111111001 09 L9 = L8 K6 mod 216 + 1 = 1111101111111001
0000011000000110 mod 216 + 1 = 1011011111101001 10 L10 = L7 + L9 mod 216 = 0111101101000000 +
1011011111101001 mod 216 = 0011001100101001 11 L11 = L1 XOR L9 = 1101000101010001 XOR 1011011111101001 =
0110011010111000 12 L12 = L3 XOR L9 = 1111101111100000 XOR 1011011111101001 =
0100110000001001 13 L13 = L2 XOR L10 = 0010000100000001 XOR 0011001100101001 =
0001001000101000 14 L14 = L4 XOR L10 = 1010000110111000 XOR 0011001100101001 =
1001001010010001 Untuk putaran berikutnya :
X1 = L11 = 0110011010111000 X2 = L12 = 0100110000001001
X3 = L13 = 0001001000101000 X4 = L14 = 1001001010010001
PUTARAN - 3 01 L1 = X1 K1 mod 216 + 1 = 0110011010111000
1010111100000000 mod 216 + 1 = 1000000111001001
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02 L2 = X2 + K2 mod 216 = 0100110000001001 + 1110110011101101 mod 216 = 0011100011110110
03 L3 = X3 + K3 mod 216 = 0001001000101000 + 1110110011101101 mod 216 = 1111111100010101
04 L4 = X4 K4 mod 216 + 1 = 1001001010010001 1000100001001100 mod 216 + 1 = 0011110100000100
05 L5 = L1 XOR L3 = 1000000111001001 XOR 1111111100010101 = 0111111011011100
06 L6 = L2 XOR L4 = 0011100011110110 XOR 0011110100000100 = 0000010111110010
07 L7 = L5 K5 mod 216 + 1 = 0111111011011100 0001001100000011 mod 216 + 1 = 1100011100101001
08 L8 = L6 + L7 mod 216 = 0000010111110010 + 1100011100101001 mod 216 = 1100110100011011
09 L9 = L8 K6 mod 216 + 1 = 1100110100011011 0000001100010011 mod 216 + 1 = 1000011110001011
10 L10 = L7 + L9 mod 216 = 1100011100101001 + 1000011110001011 mod 216 = 0100111010110100
11 L11 = L1 XOR L9 = 1000000111001001 XOR 1000011110001011 = 0000011001000010
12 L12 = L3 XOR L9 = 1111111100010101 XOR 1000011110001011 = 0111100010011110
13 L13 = L2 XOR L10 = 0011100011110110 XOR 0100111010110100 = 0111011001000010
14 L14 = L4 XOR L10 = 0011110100000100 XOR 0100111010110100 = 0111001110110000
Untuk putaran berikutnya : X1 = L11 = 0000011001000010
X2 = L12 = 0111100010011110 X3 = L13 = 0111011001000010
X4 = L14 = 0111001110110000 PUTARAN - 4
01 L1 = X1 K1 mod 216 + 1 = 0000011001000010 0111100111111000 mod 216 + 1 = 0011111011110101
02 L2 = X2 + K2 mod 216 = 0111100010011110 + 1110110011101101 mod 216 = 0110010110001011
03 L3 = X3 + K3 mod 216 = 0111011001000010 + 0111011001110111 mod 216 = 1110110010111001
04 L4 = X4 K4 mod 216 + 1 = 0111001110110000 0111111111010110 mod 216 + 1 = 1100101101011100
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05 L5 = L1 XOR L3 = 0011111011110101 XOR 1110110010111001 = 1101001001001100
06 L6 = L2 XOR L4 = 0110010110001011 XOR 1100101101011100 = 1010111011010111
07 L7 = L5 K5 mod 216 + 1 = 1101001001001100 1000000110000001 mod 216 + 1 = 1101100111101011
08 L8 = L6 + L7 mod 216 = 1010111011010111 + 1101100111101011 mod 216 = 1000100011000010
09 L9 = L8 K6 mod 216 + 1 = 1000100011000010 1000100110001001 mod 216 + 1 = 1011100001011010
10 L10 = L7 + L9 mod 216 = 1101100111101011 + 1011100001011010 mod 216 = 1001001001000101
11 L11 = L1 XOR L9 = 0011111011110101 XOR 1011100001011010 = 1000011010101111
12 L12 = L3 XOR L9 = 1110110010111001 XOR 1011100001011010 = 0101010011100011
13 L13 = L2 XOR L10 = 0110010110001011 XOR 1001001001000101 = 1111011111001110
14 L14 = L4 XOR L10 = 1100101101011100 XOR 1001001001000101 = 0101100100011001
Untuk putaran berikutnya : X1 = L11 = 1000011010101111
X2 = L12 = 0101010011100011 X3 = L13 = 1111011111001110
X4 = L14 = 0101100100011001 PUTARAN - 5
01 L1 = X1 K1 mod 216 + 1 = 1000011010101111 1001011100111100 mod 216 + 1 = 0111101001110100
02 L2 = X2 + K2 mod 216 = 0101010011100011 + 0111011001111111 mod 216 = 1100101101100010
03 L3 = X3 + K3 mod 216 = 1111011111001110 + 0111011001110111 mod 216 = 0110111001000101
04 L4 = X4 K4 mod 216 + 1 = 0101100100011001 0111100111111000 mod 216 + 1 = 1111011011000110
05 L5 = L1 XOR L3 = 0111101001110100 XOR 0110111001000101 = 0001010000110001
06 L6 = L2 XOR L4 = 1100101101100010 XOR 1111011011000110 = 0011110110100100
07 L7 = L5 K5 mod 216 + 1 = 0001010000110001 1100000011000100 mod 216 + 1 = 0010011001010000
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08 L8 = L6 + L7 mod 216 = 0011110110100100 + 0010011001010000 mod 216 = 0110001111110100
09 L9 = L8 K6 mod 216 + 1 = 0110001111110100 1100010011000000 mod 216 + 1 = 0111101000101111
10 L10 = L7 + L9 mod 216 = 0010011001010000 + 0111101000101111 mod 216 = 1010000001111111
11 L11 = L1 XOR L9 = 0111101001110100 XOR 0111101000101111 = 0000000001011011
12 L12 = L3 XOR L9 = 0110111001000101 XOR 0111101000101111 = 0001010001101010
13 L13 = L2 XOR L10 = 1100101101100010 XOR 1010000001111111 = 0110101100011101
14 L14 = L4 XOR L10 = 1111011011000110 XOR 1010000001111111 = 0101011010111001
Untuk putaran berikutnya : X1 = L11 = 0000000001011011
X2 = L12 = 0001010001101010 X3 = L13 = 0110101100011101
X4 = L14 = 0101011010111001 PUTARAN - 6
01 L1 = X1 K1 mod 216 + 1 = 0000000001011011 0001011011110010 mod 216 + 1 = 0010011111111110
02 L2 = X2 + K2 mod 216 = 0001010001101010 + 0011111101000000 mod 216 = 0101001110101010
03 L3 = X3 + K3 mod 216 = 0110101100011101 + 0011101100111100 mod 216 = 1010011001011001
04 L4 = X4 K4 mod 216 + 1 = 0101011010111001 1101001000100010 mod 216 + 1 = 1111111101100100
05 L5 = L1 XOR L3 = 0010011111111110 XOR 1010011001011001 = 1000000110100111
06 L6 = L2 XOR L4 = 0101001110101010 XOR 1111111101100100 = 1010110011001110
07 L7 = L5 K5 mod 216 + 1 = 1000000110100111 1100010011000100 mod 216 + 1 = 1011110000110110
08 L8 = L6 + L7 mod 216 = 1010110011001110 + 1011110000110110 mod 216 = 0110100100000100
09 L9 = L8 K6 mod 216 + 1 = 0110100100000100 1100010011000100 mod 216 + 1 = 0010011001011001
10 L10 = L7 + L9 mod 216 = 1011110000110110 + 0010011001011001 mod 216 = 1110001010001111
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11 L11 = L1 XOR L9 = 0010011111111110 XOR 0010011001011001 = 0000000110100111
12 L12 = L3 XOR L9 = 1010011001011001 XOR 0010011001011001 = 1000000000000000
13 L13 = L2 XOR L10 = 0101001110101010 XOR 1110001010001111 = 1011000100100101
14 L14 = L4 XOR L10 = 1111111101100100 XOR 1110001010001111 = 0001110111101011
Untuk putaran berikutnya : X1 = L11 = 0000000110100111
X2 = L12 = 1000000000000000 X3 = L13 = 1011000100100101
X4 = L14 = 0001110111101011 PUTARAN - 7
01 L1 = X1 K1 mod 216 + 1 = 0000000110100111 1010010111100000 mod 216 + 1 = 0001010000001110
02 L2 = X2 + K2 mod 216 = 1000000000000000 + 1001111110011110 mod 216 = 0001111110011110
03 L3 = X3 + K3 mod 216 = 1011000100100101 + 1001110110100000 mod 216 = 0100111011000101
04 L4 = X4 K4 mod 216 + 1 = 0001110111101011 0101001111111111 mod 216 + 1 = 1111010001000101
05 L5 = L1 XOR L3 = 0001010000001110 XOR 0100111011000101 = 0101101011001011
06 L6 = L2 XOR L4 = 0001111110011110 XOR 1111010001000101 = 1110101111011011
07 L7 = L5 K5 mod 216 + 1 = 0101101011001011 0110001001100010 mod 216 + 1 = 0101010011010010
08 L8 = L6 + L7 mod 216 = 1110101111011011 + 0101010011010010 mod 216 = 0100000010101101
09 L9 = L8 K6 mod 216 + 1 = 0100000010101101 0110001001100000 mod 216 + 1 = 0110001000000110
10 L10 = L7 + L9 mod 216 = 0101010011010010 + 0110001000000110 mod 216 = 1011011011011000
11 L11 = L1 XOR L9 = 0001010000001110 XOR 0110001000000110 = 0111011000001000
12 L12 = L3 XOR L9 = 0100111011000101 XOR 0110001000000110 = 0010110011000011
13 L13 = L2 XOR L10 = 0001111110011110 XOR 1011011011011000 = 1010100101000110
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14 L14 = L4 XOR L10 = 1111010001000101 XOR 1011011011011000 = 0100001010011101
Untuk putaran berikutnya : X1 = L11 = 0111011000001000
X2 = L12 = 0010110011000011 X3 = L13 = 1010100101000110
X4 = L14 = 0100001010011101 PUTARAN - 8
01 L1 = X1 K1 mod 216 + 1 = 0111011000001000 0100101110111111 mod 216 + 1 = 0100010100001100
02 L2 = X2 + K2 mod 216 = 0010110011000011 + 1001110110011110 mod 216 = 1100101001100001
03 L3 = X3 + K3 mod 216 = 1010100101000110 + 1100111111010000 mod 216 = 0111100100010110
04 L4 = X4 K4 mod 216 + 1 = 0100001010011101 0010110111100100 mod 216 + 1 = 1110000011100100
05 L5 = L1 XOR L3 = 0100010100001100 XOR 0111100100010110 = 0011110000011010
06 L6 = L2 XOR L4 = 1100101001100001 XOR 1110000011100100 = 0010101010000101
07 L7 = L5 K5 mod 216 + 1 = 0011110000011010 0011000100110001 mod 216 + 1 = 0110111101101110
08 L8 = L6 + L7 mod 216 = 0010101010000101 + 0110111101101110 mod 216 = 1001100111110011
09 L9 = L8 K6 mod 216 + 1 = 1001100111110011 0011000000110001 mod 216 + 1 = 1110101010001001
10 L10 = L7 + L9 mod 216 = 0110111101101110 + 1110101010001001 mod 216 = 0101100111110111
11 L11 = L1 XOR L9 = 0100010100001100 XOR 1110101010001001 = 1010111110000101
12 L12 = L3 XOR L9 = 0111100100010110 XOR 1110101010001001 = 1001001110011111
13 L13 = L2 XOR L10 = 1100101001100001 XOR 0101100111110111 = 1001001110010110
14 L14 = L4 XOR L10 = 1110000011100100 XOR 0101100111110111 = 1011100100010011
Untuk transformasi output : X1 = L11 = 1010111110000101
X2 = L13 = 1001001110010110 X3 = L12 = 1001001110011111
X4 = L14 = 1011100100010011
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TRANSFORMASI OUTPUT 01 Y1 = X1 K1 mod 216 + 1 = 1010111110000101
0100100010000101 mod 216 + 1 = 0110011001100001 02 Y2 = X2 + K2 mod 216 = 1001001110010110 + 1100111111001111
mod 216 = 0110001101100101 03 Y3 = X3 + K3 mod 216 = 1001001110011111 + 1100111011010000
mod 216 = 0110001001101111 04 Y4 = X4 K4 mod 216 + 1 = 1011100100010011
0100101110111111 mod 216 + 1 = 0110111101101011 Hasil Dekripsi :
Y1 = 0110011001100001 = fa Y2 = 0110001101100101 = ce
Y3 = 0110001001101111 = bo Y4 = 0110111101101011 = ok
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3.2. Perancangan