It works by loading all of the unique characters into an array and then changing each one to another character within that array (each one receives a unique value as well). The decrypter simply unscrambles the nonsensical output and rebuilds the exact same file you had before.
That sounds like a simple substitution encryption. The complexity of that encryption is such that's it's used as childrens puzzles to unravel "secret codes". While it has nothing to do with the problem you are facing, I do wonder, which data is sensitive enough that it needs encryption when "sending it across the internet", but is innocent enough that a home-grown substitution encryption will do?

In reply to Re: Non-ASCii character encryption by JavaFan
in thread Non-ASCii character encryption by ROFL

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