The document discusses cryptographic algorithms and keys. It describes the RC4 algorithm which uses a key stream to encrypt plaintext into ciphertext. It involves initializing a state array S with permutations, then generating a pseudo-random key stream by swapping array bytes based on the key and indices i and j. The key stream is then combined with plaintext to produce ciphertext. The document also mentions SSL and provides several references on RC4, WEP attacks, and cryptographic algorithm breakdowns.

1. AMJAD REHMAN A

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3. • ALGORITHMS CRYPTOGRAPHY
CRYPTOGRAPHIC KEYS

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11001100 plaintext
01101100 key stream
10100000 Cipher text

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for i = 0 to 255
do
S[i] = i;
T[i] = K[i mod keylen];

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j = 0;
for i = 0 to 255
do
j = (j + S[i] + T[i]) mod 256;
Swap (S[i], S[j]);

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i, j = 0;
for (int x = 0; x < byteLen; x++)
do
i = (i + 1) mod 256;
j = (j + S[i]) mod 256;
Swap (S[i], S[j]);
t = (S[i] + S[j]) mod 256;
k = S[t];

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• SECURE SOCKETS LAYER
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HTTP://WWW.DRIZZLE.COM/~ABOBA/IEEE/RC4_KSAPROC.PDF
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HTTP://WWW.CS.RICE.EDU/~ASTUBBLE/WEP/WEP_ATTACK.PDF
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HTTP://WWW.RSASECURITY.COM/RSALABS/TECHNOTES/WEP.HTML
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HTTP://WWW.NCAT.EDU/~GROGANS/ALGORITHM_BREAKDOWN.HTM
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HTTP://WWW.SCRIBD.COM/DOC/49849673/21/RC4-ALGORITHM