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SECURITY
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0058.ZIP
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PC-CODE2.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
The user in PC-DOS may list all documentation files by:
A> DIR *.DOC
Also some tips on documentation can be obtained by typing in DOS:
A> PC-HELP
PC-CODE2 is intended to encode/decode Text 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. Only printable, keybroad characters are to be used
or generated. The input and output of PC-CODE2 is line oriented;
meaning that each record can be of variable length and separated
by Carriage Return characters. PC-CODE2 deals with line oriented
data not sector oriented data as does PC-CODE1. Carriage returns
are usually generated automatically for you when you press the
ENTER or RETURN key. A Line feed character may also be generated.
To PC-CODE2 lines are physical records and they may from 0 to 255
characters in length; but for practical readability 80 characters
are usually used.
PC-CODE2 cannot encipher binary data; it is intended for
line oriented text. Each line of data must be separated
by a carriage return character. PC-CODE2 will accept and
generate printable character between CHR$(32) and CHR$(127).
The Encoded output of PC-CODE2 is suitable for printing.
There is no padding of the the input text and a header record
is added to encoded data files to indicate the version of
the program used and the time and date of encipherment.
The program will refuse to decode files it has not encoded.
PC-CODE2 code is suitable for transmission via Communications
lines without alteration.
Keys may be loaded or saved to a File (see PC-CODE1.DOC for details).
If keys are to be loaded from a file ignore the following discussion.
Two levels of security are available for either Numeric or
alphanumeric keys: "HIGH" & "LOW". It is suggested that the
first time user try "LOW" security for the first practice session.
Low security requires either 7 key numbers or 7 alphanumeric
passwords. High security requires a minimum of 25 numbers or
at least 180 characters in passwords. Low security is not
suitable to sensitive applications.
The user must provide a series of keys (a minimum of 7) which
may either be numeric (i.e. character "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. No two key numbers
should be the same (number). Examples of Numeric Keys:
GOOD KEYS ---> 1095215 348994 2127255 871101
BAD KEYS ---> 1 1 84 0
Never forget your keys, or lose them as it is impossible to
decipher the outputed code. Also, never attempt to encode