The SNOW Home Page

Whitespace steganography

The program snow is used to conceal messages in ASCII text by appending whitespace to the end of lines. Because spaces and tabs are generally not visible in text viewers, the message is effectively hidden from casual observers. And if the built-in encryption is used, the message cannot be read even if it is detected.

What's in a name?

snow exploits the steganographic nature of whitespace. Locating trailing whitespace in text is like finding a polar bear in a snowstorm (which, by the way, explains the logo). And it uses the ICE encryption algorithm, so the name is thematically consistent.

It's free!

The snow program is public domain, and source code can be downloaded from this page. There are no patents or copyrights, so its use is unrestricted. Naturally, if you do decide to use it, the author would love to hear about it.


Document written by Matthew Kwan, 9 January 1997
Please send any comments or corrections to mkwan@cs.mu.oz.au