RC4 is a symmetric stream cipher developed by Ron Rivest of RSA Data Security
Inc. The algorithm was a trade secret of RSA but was reverse engineered and
published to the internet in 1994.  RC4 is vulnerable to various attacks, and
is considered insecure.


** See Also **

   [encryption]:   

   [DES]:   

   [AES]:   

   [blowfish]:   



** Description **

'''[PT] 2004-07-01'''


The algorithm is a pseudo-random number generator with the output of
the PRNG being xored with the plaintext stream. Decryption is done
by feeding the ciphertext as input with the same key.

This cipher is included as a package in [tcllib]

e.g:

======
set src [open $filename r]
set dst [open ${filename}.rc4 w]
rc4::rc4 -key Secret -in $src -out $dst
close $src
close $dst
======

or just

======
set crypt [rc4::rc4 -key Secret {Hello, World!}]
======

<<categories>> Cryptography | Security