1. A toy example for RC4

2. A toy example for RC4. Initial state /* Initialization */
for i = 0 to 3 do
S[i] = i;
T[i] = K[i mod keylen];
S (state) 1 2 3
T for 𝑘=2

3. A toy example for RC4 /* Initial Permutation of S */ 1st update
j = 0;
for 𝑖=0 to 3 do
𝑗= 𝑗+𝑆 𝑖 +𝑇 𝑖 𝑚𝑜𝑑 4 ;
Swap (𝑆 𝑖 ,𝑆 𝑗 );
For 𝑖=0, 𝑗=0 we get: 𝑗=0+0+2≡2 𝑚𝑜𝑑 4 : 𝑆 𝑖=0 =0, 𝑆 𝑗=2 =2
1st update
For 𝑖=1, 𝑗=2 we get: 𝑗=2+1+2≡1 𝑚𝑜𝑑 4 : 𝑆 𝑖=1 =1, 𝑆 𝑗=1 = nd update
For 𝑖=2, 𝑗=1 we get: 𝑗=1+0+2≡3 𝑚𝑜𝑑 4 : 𝑆 𝑖=2 =0, 𝑆 𝑗=3 =3
3rd update
For 𝑖=3, 𝑗=3 we get: 𝑗=3+0+2≡1 𝑚𝑜𝑑 4 : 𝑆 𝑖=3 =0, 𝑆 𝑗=1 =1
4th update
State 𝑺 (𝒊=𝟎) 2 1 3
State 𝑺 (𝒊=𝟏) 2 1 3
State 𝑺 (𝒊=𝟐) 2 1 3
State 𝑺 (𝒊=𝟑) 2 3 1

4. A toy example for RC4 /* Stream Generation */
i, j = 0;
while (true)
j = (j + S[i]) mod 4;
i = (i + 1) mod 4;
Swap (S[i], S[j]);
t = (S[i] + S[j]) mod 4;
k = S[t];
For 𝑖=0, 𝑗=0: 𝑗=0+2≡2 𝑚𝑜𝑑 4, 𝑖=1; 𝑆 𝑖=1 =0, 𝑆 𝑗=2 =3.
Update, compute 𝑡=3 and output 𝑆 3 =1
For 𝑗=2, 𝑖=1: 𝑗=2+3≡1 𝑚𝑜𝑑 4, 𝑖=2; 𝑆 𝑖=2 =0, 𝑆 𝑗=1 =3.
Update compute 𝑡=3, and output 𝑆 3 =1
For 𝑗=1, 𝑖=2: 𝑗=1+3≡0 𝑚𝑜𝑑 4, 𝑖=3; 𝑆 𝑖=3 =1, 𝑆 𝑗=0 =2.
Update compute 𝑡=3, and output 𝑆 3 =2
State 𝑺 2 3 1
State 𝑺 2 3 1
State 𝑺 1 3 2