Re: and now for something completely different.



Antony Clements <antony.clements@xxxxxxxxxxxxxxx> wrote:
how effective is this method?

[...] Cj = Pj xor Kj xor Ci
[...]
where j and i are counters. this is a byte by byte method. assume that P, C
and K are the same length.

Except for the pointless addition of the previous ciphertext byte this
is a stream cipher.

--
Kristian Gjøsteen
.



Relevant Pages

  • Re: Pls help
    ... I have designed one stream cipher ... The length of sequence will depend on the ... >>bitsusing the XOR operation. ... involve the state bits from two of the registers. ...
    (sci.crypt)
  • Re: Packet timing to send key bits
    ... >influence the packet timings in some manner. ... >XOR with the stream cipher, ... Seems to me an eavesdropper ...
    (sci.crypt)
  • Re: and now for something completely different.
    ... cj = Pj xor Kj xor Ci ... which is, as Kristian pointed-out, is an ordinary stream cipher. ... if K_j is a secure key stream, ...
    (sci.crypt)
  • Re: RC4 on AMD64
    ... ]> Just as no cipher withstands a reveal-the-key attack, no stream cipher ... ]> withstands an XOR attack. ...
    (sci.crypt)
  • Re: block cypher from a hash function?
    ... > That description is a stream cipher anyway. ... Well, yes, sort of. ... Make new hashes from the created ciphertext+key and ... use it to XOR the next block of plaintext etc. etc. etc. ...
    (sci.crypt)