A canary trap is a method for exposing an information leak by giving different versions of a sensitive document to each of several suspects and seeing which version gets leaked.
The term was coined by Tom Clancy in his novel Patriot Games, although Clancy did not invent the technique. The actual method (usually referred to as a Barium meal test in espionage circles) has been used by intelligence agencies for many years. The fictional character Jack Ryan describes the technique he devised for identifying the sources of leaked classified documents:
Each summary paragraph has six different versions, and the mixture of those paragraphs is unique to each numbered copy of the paper. There are over a thousand possible permutations, but only ninety-six numbered copies of the actual document. The reason the summary paragraphs are so lurid is to entice a reporter to quote them verbatim in the public media. If he quotes something from two or three of those paragraphs, we know which copy he saw and, therefore, who leaked it.
A refinement of this technique uses a thesaurus program to shuffle through synonyms, thus making every copy of the document unique.
Read more about Canary Trap: Barium Meal Test, Embedding Information, In Popular Culture
Famous quotes containing the words canary and/or trap:
“Cruelty is a mystery, and the waste of pain. But if we describe a word to compass these things, a world that is a long, brute game, then we bump against another mystery: the inrush of power and delight, the canary that sings on the skull.”
—Annie Dillard (b. 1945)
“And boys, be in nothing so moderate as in love of man, a clever
servant, insufferable master.
There is the trap that catches noblest spirits, that
caught—they say—God, when he walked on earth.”
—Robinson Jeffers (1887–1962)