There's quite a few books...my favorite being Tesla: Master of Lightning. Anyway, neither was "well-rounded" by todays terms. Tesla was obsessive-compulsive and couldn't stand to be dirty, had problems with doing everyday things like turning off water faucets, etc. Edison was the complete opposite, and would only shower and eat at the forceful hand of his wife:-).
This method is a steganographic method and a common misconception is that steganography is meant to replace cryptography (or the other way around since steg. was first:-p). That's not the case...they supplement eachother. If the information you're sending is encrypted with a strong encryption algorithm, nothing but a perfect extraction will be useful. The location of the embeded information in the noise can be key-based, which makes it harder to find. After extracting the information, the unencryption process is key-based as well. Currect cryptographic methods are developed so that if even one bit of the ciphertext changes, approximately half the bits in the unencrypted message change, which means none of this 'It's not perfect' or 80% is gonna work.
I have to disagree at a couple points. First of all, it's very possible to have a steganographic method which hides the hidden message in such a way that even with the stegoimage and the cover-image, the message cannot be retrieved (image here means object...it can be a picture, or a sound, or a disk...it doesn't matter). Secondly, good cryptographic algorithms do (are supposed to) produce output which meets relatively rigorous psuedo-random standards. Third, and last, I would say this is steganography, since it is hidden a message in another message...there are currently accepted steganographic methods which use manipulated noise to transmit the message. I would consider noise a message, in that it takes information (even useless information), from one point to another.
Hi there... I don't post must, so bear with me here...I'm kind of stupid. I'm doing a research/development segment on steganography and I just thought I could contribute something to your question. Steganography is the art of concealing a message (and it's existance) within another seemingly normal message. That means, not only are images used in steganography. Steganography has been around for well longer then cryptography (the first recorded cryptographic method was ceasar shifting letters 4 to the write to 'encode' a message. The first recorded steganographic instance is in greek mythology...they would write on wax tablets with wooden bases and someonen scraped the wax off, carved a message on the wood, and re-waxed the board so it would pass inspection). Steganography doesn't have to be in images...it can be pin pricks on a typed page, invisible ink, microdots (an ingenious german invention in WWII which cramed the clarity of a typed page into the size of a typed period) or letter grilles. From my understanding of the above technology it is nothing other then relatively elementary steganography. For clarification, digital steganography does not require 'cover-image escrow' as it's called. It's not always required that you subtract the original image from the stego-image in order to obtain a copy of the stego-message...some algorithms are key based, and some theories suggest adding the stego-message as digital image distortions which can be removed using digital image correction software, thus producing the original which can be subtracted for the noised image. Steganography doesn't always have to be used to hide a secret message in transport either. It's most forcused application now-a-days is that of digital watermarking to track the origin of something like an audio bit (humans cannot recognize very very close echos...) and images. Another common application is tamperproofing, so that data cannot be changed without someone realizing it.
Anyway...all I was really saying is that this is steganography and it's hardly a new concept. Embassy encrypted hardlines have done something very similar to this for years in which they transmit psuedo-random data across the line at all times so that when an encrypted message is sent, the enemy doesn't know (a good cryptographic protocol will produce a ciphertext which at least closely resembles a random set of information).
I don't know how it works either, but I have seen such a thing advertised. I was thinking that perhaps the phone systems work in such a way that an inaudible signal is sent to indicate things such as a connection or the fact that it is busy, as well as actually playing the audible busy signal. If this were the case, the phone box thing could 'cause the signal which indicates a disconnected number to be sent, which would cause the telemarketer's computer to believe the number no longer worked and to take it out of their system. That's actually probably a stupid idea...I don't see why the phone companies would allow such things to take place. Just a thought though.
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There's quite a few books...my favorite being Tesla: Master of Lightning. Anyway, neither was "well-rounded" by todays terms. Tesla was obsessive-compulsive and couldn't stand to be dirty, had problems with doing everyday things like turning off water faucets, etc. Edison was the complete opposite, and would only shower and eat at the forceful hand of his wife :-).
--Reltuk
This method is a steganographic method and a common misconception is that steganography is meant to replace cryptography (or the other way around since steg. was first :-p). That's not the case...they supplement eachother. If the information you're sending is encrypted with a strong encryption algorithm, nothing but a perfect extraction will be useful. The location of the embeded information in the noise can be key-based, which makes it harder to find. After extracting the information, the unencryption process is key-based as well. Currect cryptographic methods are developed so that if even one bit of the ciphertext changes, approximately half the bits in the unencrypted message change, which means none of this 'It's not perfect' or 80% is gonna work.
--Reltuk
I have to disagree at a couple points. First of all, it's very possible to have a steganographic method which hides the hidden message in such a way that even with the stegoimage and the cover-image, the message cannot be retrieved (image here means object...it can be a picture, or a sound, or a disk...it doesn't matter). Secondly, good cryptographic algorithms do (are supposed to) produce output which meets relatively rigorous psuedo-random standards. Third, and last, I would say this is steganography, since it is hidden a message in another message...there are currently accepted steganographic methods which use manipulated noise to transmit the message. I would consider noise a message, in that it takes information (even useless information), from one point to another.
--Reltuk
Hi there...
I don't post must, so bear with me here...I'm kind of stupid. I'm doing a research/development segment on steganography and I just thought I could contribute something to your question. Steganography is the art of concealing a message (and it's existance) within another seemingly normal message. That means, not only are images used in steganography. Steganography has been around for well longer then cryptography (the first recorded cryptographic method was ceasar shifting letters 4 to the write to 'encode' a message. The first recorded steganographic instance is in greek mythology...they would write on wax tablets with wooden bases and someonen scraped the wax off, carved a message on the wood, and re-waxed the board so it would pass inspection). Steganography doesn't have to be in images...it can be pin pricks on a typed page, invisible ink, microdots (an ingenious german invention in WWII which cramed the clarity of a typed page into the size of a typed period) or letter grilles. From my
understanding of the above technology it is nothing other then relatively elementary steganography. For clarification, digital steganography does not require 'cover-image escrow' as it's called. It's not always required that you subtract the original image from the stego-image in order to obtain a copy of the stego-message...some algorithms are key based, and some theories suggest adding the stego-message as digital image distortions which can be removed using digital image correction software, thus producing the original which can be subtracted for the noised image. Steganography doesn't always have to be used to hide a secret message in transport either. It's most forcused application now-a-days is that of digital watermarking to track the origin of something like an audio bit (humans cannot recognize very very close echos...) and images. Another common application is tamperproofing, so that data cannot be changed without someone realizing it.
Anyway...all I was really saying is that this is steganography and it's hardly a new concept. Embassy encrypted hardlines have done something very similar to this for years in which they transmit psuedo-random data across the line at all times so that when an encrypted message is sent, the enemy doesn't know (a good cryptographic protocol will produce a ciphertext which at least closely resembles a random set of information).
--Reltuk
I don't know how it works either, but I have seen such a thing advertised. I was thinking that perhaps the phone systems work in such a way that an inaudible signal is sent to indicate things such as a connection or the fact that it is busy, as well as actually playing the audible busy signal. If this were the case, the phone box thing could 'cause the signal which indicates a disconnected number to be sent, which would cause the telemarketer's computer to believe the number no longer worked and to take it out of their system. That's actually probably a stupid idea...I don't see why the phone companies would allow such things to take place. Just a thought though.
--Reltuk