$Hidden Messages In Bitcoin Blockchain

Things only become really futile when you give up hope in them.

Encryption works and it works well. There are flaws in everything. And Hyper-powers with unlimited funds, can try to place holes in some methods, and have unlimited resources and trained attackers to target data. If the NSA or KGB wants to find information on you, they'll get it.

But cryptography is very strong. The stated purpose of that data center in Utah is to make attacking AES-256 possible within an actionable time-frame by 2018. This probably means 2015, but there aren't magic keys. Simply collisions. What this encryption means is the powers that be have to spear fish for data. Not cast a net and gobble it all up.

In an ideal world this means that the effort will be spent to hunt down pedophiles and people who want to blow things up, and not used by politicians to spy on their girlfriends. I am of course, very aware we don't live in an ideal world.

Interestingly enough, mathematical perfect secrecy has existed in cryptography since the 19th century. It's a one-time pad. Basically you and I agree on a secret private key that we exchange where nobody see's it. We use that key only once when we speak over a public channel. Then the key is destroyed. It's complete entropy, there is nothing to compare it to, and is mathematically unsolvable. It's how the Zodiak killer wrote those 'mystery' letters. He wasn't brilliant, it was simply total entropy.

However, this is extremely impracticable. It requires a secret channel. So we use public keys and as much entropy as a computer can muster to generate suitably complex asymmetric keys, despite the drawback of this always allowing this cat and mouse game.

There's actually a solution in quantum cryptography. Perfect secrecy. By physical laws (Heisenberg) it allows you to ensure that your channel to exchange your one time pad is truly secure. If one were to attempt to eavesdrop upon this conversion, they would not be able to without altering the quantum state of the original message.

 

no, it just rewrites the inodes. in fact, that's all a format operation does is write the inodes to the disk. inodes tell the kernel which logical block address to look to find the beginning of a file. the rest of the partition is untouched by a format operation. of course the data is still there because reformatting does not rewrite all blocks on the device. writing out to the entire device would be quite slow and unnecessary. you can however overwrite all blocks of the device with zeros, or better, psuedorandom bytes and i guarantee that it's not recoverable through software means. writing zeroes to the entire device will leave one with a device containing no filesystem, and no partitions.

there is a mostly theoretical method to recover the previous state of single bits involving an electron microscope with some probability. however this has only been shown to be somewhat feasible with magnetic storage of very low recording density using MFM/RLL encoding, closer to the storage density of a 1.44MB floppy disk than a modern high capacity hard drive, which also use much more complicated encoding schemes, making recovering a single isolated bit infeasible without knowing many consecutive bits already.

also it should be noted that this is only for *single bits* and the probability of success decrease exponentially as you attempt to recover consecutive bits .. recovering even a whole byte is almost impossible. with the storage density of hard drives today, this is almost inconceivably infeasible.