Re: An Honest and Simple Question.



On 16 Jul., 08:03, adacrypt wrote:
My question is this:  How in general, in modern Western cryptography
is textual data for encryption entered into a computer.

Why don't you try to find this out by yourself ?
Have a look at GPG, TLS, ...
http://www.gnupg.org/
http://en.wikipedia.org/wiki/Transport_Layer_Security

I am speaking of ordinary plaintext from the
character set of printable ASCII.

Character set doesn't matter. "plaintext" (as used in cryptography)
doesn't imply a special encoding (ASCII, Unicode, ...). It just refers
to the *encoded message* with whatever encoding you choose (could be a
GZip-compressed stream of UTF-8 text or a JPEG image).

It's been said already. You're mixing two or three things together
that should have been handeled separately: encoding, encryption,
armoring.

My own ciphers are designed to 1) handle large-volume secure
communications by reading plaintext in from external batch files and
writing out the ciphertext that emanates from the encryption to
another dedicated external file that may then be transmitted by
electronic means

This is nothing new. See GPG, 7zip, ...

and  2) short impromptu email messages are keyed in
from the keyboard in interactive mode, encrypted, and the ciphertext
is then written to an external file for transmission by electronic
means.

To me this seems the obvious thing to do.  I can’t understand why I am
being admonished to read bytes instead of plaintext as it appears.

I think your confusion comes from the fact that you think "plaintext"
implies human readable text encoded using ASCII. This is not the case.
It's much more convenient to treat your plaintexts and ciphertexts as
sequences of octets -- regardless of their encoding.

What gives here? - adacrypt

I don't know. For some reason you seem to be immune to well-reasoned
criticism. For some reason you seem to think your ciphers are worth
investigating / using.

I guess you should really try to understand why only crazy hobby
cryptographers try to "optimize the OTP". Once you realized that
anything as "safe" as the OTP is as useless you should focus on
current state of the art methods (see block ciphers like AES). You
might also want to take a look at how other applications handle all
this. For example, try to figure out what happens if you use GPG in
its symmetric mode (option "-c").

Cheers!
SG
.



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