![]() ![]() Some log files, instead of presenting binary data from an application in the text file itself, will base64-encode the data and then put the encoded data into the log file. ![]() Sending MIME messages (attachments of e-mail are sent this way) uses base64-encoding so that binary data is not sent to the receiving SMTP server as I recall. BASE64 ENCODING FROM COMMAND LINE HOW TOAnybody who has used Lightweight Directory Access Protocol (LDAP) for more than a day likely has seen blocks of text about seventy-six characters in length though they may not have figured out how to present the data in a human-understandable form. Ciphers use math to make the data irretrievable unless a mathematically-relevant key is used (the same that created the enciphered data, or one that is made specifically to decrypt the enciphered data) and encoding uses math to change the presentation of the data from one form to another, though not for purposes of hiding it from a third party.īase64-encoding is used in many other parts of computing. The point behind all of this is that encoding is not meant to prevent data from being seen, and enciphering is. ![]() The more data the easier this type of “decoding” but that’s the general idea. Anyway, notice that the “bb” characters occur for the two ‘o’ characters in ‘Troops’ which also means that this type of encoding can be broken using mathematics certain letters occur in certain percentages in regular communication so certain letters, when showing up as the most-common in an encoded string, can be assumed to be these most-common characters in the cleartext string. Use this in a time when encoding is brand new and computers are not around and it’s a bit more tricky. Consider the line, “moveTroopsNorth” using this simple encoding and you end up with “zbirGebbcfAbegu” which looks terrible but really isn’t that terrible to break since you can try all twenty-five combinations of rotation encodings (assuming you stick with just alphabetic characters) in a fraction of a second with a computer. If you “rotate” every character you want to send by thirteen other characters you can hide data from an unmotivated or uneducated thirty party fairly quickly and that is what was done. In the English alphabet there are twenty-six characters so half of that is thirteen. The name comes from the word Rotation and the number of places characters were “rotated”. This was done back long before computers came into being, unsurprisingly, for political purposes to hide data from untrusted parties while transferring it between two other trusted parties. So going back to the bit about encoding and enciphering consider an early use of encoded data, the ROT-13 encoding. ![]()
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