Tuesday, July 6, 2010

Hiding Quantum Information in the Perfect Code

Todd Brun and I have posted our new paper on arXiv entitled, "Hiding Quantum Information in the Perfect Code." You can find the paper here. I have reproduced the abstract below:

We present and analyze a protocol for quantum steganography where the sender (Alice) encodes her steganographic information into the error syndromes of the perfect (five-qubit) quantum error-correcting code, and sends it to the receiver (Bob) over a depolarizing channel. Alice and Bob share a classical secret key, and hide quantum information in such a way that to an eavesdropper (Eve) without access to the secret key, the quantum message looks like an innocent codeword with a typical sequence of quantum errors. We calculate the average rate of key consumption, and show how the protocol improves in performance as information is spread over multiple codeword blocks. Alice and Bob utilize different encodings to optimize the average number of steganographic bits that they can send to each other while matching the error statistics of the depolarizing channel.

2 comments:

nethmi said...

are the steganography and the encoding (pub key & pvt key) equal?

I read a article on


http://hareenlaks.blogspot.com/2010/05/what-is-steganography.html


which says they are equal but I'm not sure . what is you idea.

The Quantum Poet said...

@Nethmi
If you are asking whether steganography and cryptography are equal, then the answer is no they are not. In the former the sender hides the message in plain view of an eavesdropper, while in the latter the message is encrypted and transformed so that it looks like garbage to the eavesdropper.