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PC-CODE1.DOC
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1984-02-09
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To begin execution of PC-CODE1 or PC-CODE2, just type these names
in PC DOS or type PC-MENU. For example: "A> PC-MENU "
PC-CODE1 is intended to encode/decode files only. It does this
thru a process known as super-encipherment. This means that
each character of plain text (uncoded text) is both scrambled
(transposed) as well as substituted for some random "other"
character.
Keys may Optionally be Loaded or Saved to a FILE. The data format
of such a file is 25 KEY numbers (between 1 & 2,147,483,646)
each separated by A Carriage Return (on separate lines); And
finally a 26th line of required Comment/Remark Information.
An example of a key file is "SAMPLE.KEY". You can display
this file by typing one of the following in DOS.
A> TYPE SAMPLE.KEY
<OR>
A> COPY SAMPLE.KEY LPT1:
A key file may be generated in PC DOS by the Following:
A> COPY CON: MYKEY.KEY
2028841238
156091745
1551901393
590357944
..........
.......... [a total of 25 numbers]
..........
109941534
2110010604
* This is my remarks 01/31/84 7:56 PM PC-CODE1 V1.50
^Z {Ctrl-Z} {ENTER}
If a key file is not used the following discussion applies:
There are two levels of security "LOW" and "HIGH". If you
elect the LOW level you will only have to enter 7 key
(SEED) numbers or in the case of alphanumeric keys 7
passwords of 5 or more characters. Actually, the longer
the passwords - the better. An Ideal password length would
seven passwords of 8 characters each.
If you elect HIGH security be prepared to enter up to 25
numbers between 1 and 2,147,483,646; or a minimum of 180
characters of alphanumeric passwords. It is best, the first
time thru to elect LOW security for testing purposes.
Why so many characters are required in the HIGH ALPHA mode security
is due to the additional insecurity of letters/words/phrases
and that the Randomizing (hashing) routine requires 6 characters
to generate a uniformly random Number (used internally). If the
users' alphanumeric passwords were perfectfully random and
all 256 possible characters could be typed at a 47 key keybroad,
there would only be a need for 4 characters to generate this number.
The user must provide a series of keys (a minimum of 7) which
may either be numeric (i.e. characters "0123456789") or
alphanumeric which includes any character on your IBM PC
keybroad. This includes alphabetics, numerics, and special
symbols like "!@#$%^&*()=+?:.<>[]~{}" and so forth.
Each of these keys should be chosen at random, and each
should be different. For alphanumeric keys, the following
is a good example:
GOOD KEY ---> "Z$x!Un{y%C2&>"
BAD KEY ---> "ENGLISH WORDS"
It is very poor to use anything that could be found in a
dictionary or encyclopedia for a key.
For Numeric keys, the best choices might numbers chosen
randomly from a telephone book or a serial numbers on a
Dollar bill. It is considered unprofessional to use numbers
like - you birth date; social security number; or Military
service numbers. Of course, for testing numbers like 1,2,3,4,
5,6,7 are great to test out the programs. Example of keys:
GOOD KEYS ---> 1095572 6712950 4007173 935506
BAD KEYS ---> 1 1 84 0
INVALID ---> 1,000,000 7.712355 -679811 6566710-
Note that it is Invalid to include commas within key numbers.
Also, note that numeric keys are positive Integers greater
than zero. For best results, numeric keys should be 6 digits
at least.
Input and output must be to and from a valid IBM PC file.
The same file may be used for both input and output for PC-CODE1
only. This is however, not recommended. Input/output must NOT
the Console or Printer. PC-CODE1 supports only File Input/Output.
Never forget your keys, or lose them as it is impossible to
decipher the outputed code. Also, never attempt to encode