Bitcoin Explanation - Schneier on Security

Bitcoin Civil War (the bright sides)

It will be interesting to see how the next couple of months play out. Whatever happens, there are a couple of positive sides to the situation.
For one, we will see if it is possible to change the rules of the Bitcoin network even against considerable resistance.
The Japanese Constitution has never been amended. But it is very clear what is necessary to amend it. Article 96 of the Constitution states the requirements.
The Bitcoin network has never been challenged by an internal faction in the way it is now. In contrast to the Japanese Constitution, it is not very clear what is needed to push through the block size extension the Bitcoin Unlimited camp wants.
So if they succeed in their attempt, we will have a reference case what is needed to change the protocol against substantial resistance. If they fail, we will have a reference case as well, showing that the failed level of support was not enough.
This civil war will also be an interesting case to study when preparing for war with outside attackers. There has been speculation about "51%-attacks" before. But as far as I know, no one has ever actually pulled off a 51%-attack against the Bitcoin network.
In the course of this civil war, that may change. I hear that Peter Rizun, one of the supporters of Bitcoin Unlimited, is advocating for using hash power to shut down the original Bitcoin chain after a fork, mining empty blocks on that chain.
If that happens, that would be an excellent test case. A highly motivated, well-funded adversary trying to shut down the Bitcoin blockchain has not happened yet in real life.
If such an attack happens, and the Bitcoin blockchain survives it one way or another, that would be real-life proof of its resiliency.
Since all of the value of the Bitcoin blockchain comes from this resiliency against attack and the trust created, surviving such a test would be proof of its value. An eight year track record of unbroken service is valuable, but extending it defeating serious attacks shows even more value.
All cryptography has value only as far as people actually try to break it and fail (Schneier's law). It follows that attacks on the Bitcoin network like the one Rizun wants to happen are a good thing.
We also may get a short-term increase in block space (if the Bitcoin Unlimited faction wins the civil war).
Again, interesting times for the Bitcoin network.
submitted by Karl-Friedrich_Lenz to btc [link] [comments]

Cryptographic reviews of bitcoin?

I'm searching for informed bitcoin reviews, infact I haven't the knowledge to complitely understand and value its security, the only cryptographer that I read that write on this is Bruce Schneier, that wrote this:
"I'm often asked what I think about bitcoins. I haven't analyzed the security, but what I have seen looks good. The real issues are economic and political, and I don't have the expertise to have an opinion on that."
experienced people reviews of bitcoin
1 - Bruce Schneier
2 - Dan Kaminsky
submitted by pietrod21 to Bitcoin [link] [comments]

Writing a book on Bitcoin and blockchain technology, and I'm looking for particularly illuminating arguments for why it's taken as a given that a hostile attacker can't mass enough computing power to perform a 51% attack. Any help appreciated!

Hey all! As the title says, I'm working on a book about Bitcoin, blockchain tech, and cryptocurrencies. The section I'm working on now is about how the blockchain provides such robust security.
Bitcoin takes as a given that honest nodes will always control a majority of the computing power. To a reader who is unfamiliar with the space, though, this seems like an unsubstantiated claim. I have a vague understanding of why this is true, but I can't find a way to express it in a way that would be convincing to a layperson. Is anyone aware of any particularly illustrative examples of why this assumption is taken for granted among the Bitcoin community?
As an example of what I'm looking for, here is an illustration I'm using to demonstrate the security of a single Bitcoin private key, adapted from Bruce Schneier's writing (ctrl+f "second law of thermodynamics"):
First, recognize that a specific consequence of the second law of thermodynamics is that there is a minimum energy required to change a single binary bit of information.
Now suppose you were able to harness the entire energy output of the sun only to power a specially designed computer, whose job is to count through private keys, in the hopes of finding one corresponding to a public key that held Bitcoins.
Using a bit of math, you'll find that a perfectly efficient computer can count through 2178 values given the sun's entire annual energy output. If we divide this value into the number of possible private keys, 2256, we find that this hypothetical computer would only be able to count through 0.0000000000000000000003% of the total number of possible private keys, given the entire annual energy output of the sun.
Furthermore, this is just counting, and doesn't actually include the monumentally more complex task of actually checking each private key to see if it corresponds to a “winning” public key. So in the 0.0000000000000000000003% chance this computer did happen across a lucky private key, it wouldn't even know it.
Schneier closes with this: “These numbers have nothing to do with the technology of the devices; they are the maximums that thermodynamics will allow. And they strongly imply that brute-force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space.”
submitted by coinop-logan to Bitcoin [link] [comments]

[ PATRIOT PRAYER RALLY PORTLAND ] - GLOOMTUBE HAPPENINGWATCH - 8/4/18 Let's Talk Bitcoin! #260 New Growth The hidden trends in the jobs data Blockchain: Distributed Trust - Bart Preneel YouTube

With Bitcoin, the value is pure speculation, and halving the number basically means intentionally deleting transactions from the transaction log, which means losing all confidence and making it worthless. Dave • December 10, 2013 2:23 PM Newstechnica has a much better explanation. Tom • December 11, 2013 1:51 AM @Anura: Of course one wouldn’t delete past transactions, but simply modify ... Bruce Schneier, Image from IT Pro Today. He is correct. Within the definition of trust that Bruce provides is perhaps the reason why he can’t see why public blockchains are more than a means of speculation. The level of trust that the under 30 crowd has in public institutions and big corporations is low. Bruce Schneier is a security technologist who teaches at the Harvard Kennedy School. He is the author, most recently, of Click Here to Kill Everybody: Security and Survival in a Hyper-Connected World. But you still have to trust bitcoin — and everything about it. Much has been written about blockchains and how they displace, reshape, or eliminate trust. But when you analyze both blockchain and trust, you quickly realize that there is much more hype than value. Blockchain solutions are often much worse than what they replace. First, a caveat. His definition of a ‘public blockchain’ would apply to a blockchain like Bitcoin or Ethereum, but not a platform like the IBM Food Trust. Better not to s%#@ where you eat I suppose. Bruce Schneier Has a Curious Worldview. Here is Bruce’s word on trust, “Trust is essential to society. As a species, humans are wired to trust one another ...

[index] [12569] [38132] [12112] [11466] [12197] [29187] [29778] [34875] [39555] [45074]


Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Julia Coronado, founder and president of MacroPolicy Perspectives talks about the hidden trends behind the jobs data. -----... 014 Keynote Can Blockchain Technology Solve The Social Problem Bruce Schneier by Blockchain ... Ethereum Is A Hub Of Innovation Not A Store Of Value? - Hudson Jameson Interview by Crush The Street ... TONIGHT - CHAT RULES - NO THREATS/CALLS FOR VIOLENCE Paypal Donations - Bitcoin Donations - 1DsdnxZhnQU9q52P6sVsWUESeVatMtcK6X Ethereum D... Bitmain yesterday released the S15 and T15. These Sha256 Bitcoin miners are getting shipped from December. At the time of writing, the S15 has been sold out. Referenced: Bitmain Antminer S15 ...