I presume that if a message can be “overhear,” electronically or otherwise, it is likely the NSA and other “fictional” groups are capturing it.
The use of encryption marks you as a possible source of interest.
You can use image-based steganography to conceal messages but that requires large file sizes and is subject to other attacks.
Professor Abdelrahman Desoky of the University of Maryland in Baltimore County, USA, suggests that messages can be hidden in plain sight, but changing the wording of jokes to carry a secret message.
Desoky suggests that instead of using a humdrum text document and modifying it in a codified way to embed a secret message, correspondents could use a joke to hide their true meaning. As such, he has developed an Automatic Joke Generation Based Steganography Methodology (Jokestega) that takes advantage of recent software that can automatically write pun-type jokes using large dictionary databases. Among the automatic joke generators available are: The MIT Project, Chuck Norris Joke Generator, Jokes2000, The Joke Generator dot Com and the Online Joke Generator System (pickuplinegen).
A simple example might be to hide the code word “shaking” in the following auto-joke. The original question and answer joke is “Where do milk shakes come from?” and the correct answer would be “From nervous cows.” So far, so funny. But, the system can substitute the word “shaking” for “nervous” and still retain the humor so that the answer becomes “From shaking cows.” It loses some of its wit, but still makes sense and we are not all Bob Hopes, after all. [Hiding Secret Messages in Email Jokes]
Or if you prefer the original article abstract:
This paper presents a novel steganography methodology, namely Automatic Joke Generation Based Steganography Methodology (Jokestega), that pursues textual jokes in order to hide messages. Basically, Jokestega methodology takes advantage of recent advances in Automatic Jokes Generation (AJG) techniques to automate the generation of textual steganographic cover. In a corpus of jokes, one may judge a number of documents to be the same joke although letters, locations, and other details are different. Generally, joke and puns could be retold with totally different vocabulary, while still retaining their identities. Therefore, Jokestega pursues the common variations among jokes to conceal data. Furthermore, when someone is joking, anything may be said which legitimises the use of joke-based steganography. This makes employing textual jokes very attractive as steganographic carrier for camouflaging data. It is worth noting that Jokestega follows Nostega paradigm, which implies that joke-cover is noiseless. The validation results demonstrate the effectiveness of Jokestega. is only available to individual subscribers or to users at subscribing institutions. [Jokestega: automatic joke generation-based steganography methodology by Abdelrahman Desoky. International Journal of Security and Networks (IJSN), Vol. 7, No. 3, 2012]
If you are interested, other publications by Professor Desoky are listed here.
Occurs to me that topic maps offer the means to create steganography chains over public channels. The sender may know its meaning but there can be several links in the chain of transmission that change the message but have no knowledge of its meaning. And/or that don’t represent traceable links in the chain.
With every “hop” and/or mapping of the terms to another vocabulary, the task of statistical analysis grows more difficult.
Not the equivalent of highly secure communication networks, the contents of which can be copied onto a Lady Gaga DVD, but then not everyone needs that level of security.
Some people need cheaper but more secure systems for communication.
Will devote some more thought to the outline of a topic map system for hiding content in plain sight.