Bitcoin is a digital peer-to-peer currency with no central authority. It was created in 2009 by Satoshi Nakamoto. Transactions are managed entirely by the network.
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Could one prevent double spending in decentralized digital currencies (like Bitcoin) without all transactions being public?
A recent approach to creating a decentralized online currency, called Bitcoin, has been generating some interest. The goal is to have a way to transfer currency without a central authority and without ...
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How secure is the Bitcoin protocol?
Are there any evidence (other than not being cracked so far) that the Bitcoin protocol is secure? "How secure" is it?
(I realize that this might not qualify as a meaningful question - feel free to ...
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1answer
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How to provide secure “vanity” bitcoin address service?
Bitcoin addresses are RIPEMD-160 hashes of the public portion of a public/private ECDSA keypair (along with an abbreviated hash of the hash to provide a check code, as @pulpspy notes in a comment). ...
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Bitcoin Research
I have recently been assigned to advise a student on a senior thesis in math. She has taken linear algebra, introductory real analysis, basic cryptography, and abstract algebra. Her interest is in ...
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Is there some way to generate a non-predictable random number in a decentralised network?
Is there a way to generate a random number with given restrictions:
It will be used in a decentralised network with a big number of peers (no central authority to generate it)
Its generation should ...
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2answers
908 views
SHA-256 “midstate”
Recently I've been trying to implement some Bitcoin-related code, and I've stumbled upon a weird concept, a SHA-256 "midstate". Some explanation is given here.
The general concept is that Bitcoin ...
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0answers
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Elliptic curve cryptography related key attacks
This question is an extension of Families of public/private keys in elliptic curve cryptography
As described above, bitcoin "type 2" deterministic wallets use a root private/public key pair, where ...
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1answer
242 views
Families of public/private keys in elliptic curve cryptography
I'm looking for a related key scheme for elliptic curve cryptography. The basic idea would be that there would be a master public key and a master private key. From the master public key, you could ...
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1answer
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Ideal passphrase length: old diceware method (5 words) vs. your Bitcoin wallet.dat passphrase lenght (8 words) and doubling passwords?
I made a cool 5 word passphrase back then using the old Diceware method and use it as a master password. The question is as computing power increases will we need to add more and more words to our ...
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2answers
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Where can I learn basic cryptography to know more about passwords and Bitcoin?
Basically my knowledge in passwords consist of setting up a Diceware master password back then, and I know hashes are not convertible back to the original password.
Some basic question I want to know ...
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1answer
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How can a key pair be derived from an arbitrary hash?
If I correctly understand the concept of a "brain wallet" in BitCoin, you start with a passphrase, generate the hash of the passphrase, then somehow derive a public / private key from that to use as ...
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1answer
179 views
Storage of Private Keys
I'm building a bitcoin web application that will require all users to be assigned a wallet for adding funds to their account. I plan on exposing the public key to the user (the bitcoin address). Users ...
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1answer
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Bitcoin, couldn't a miner steal money? [closed]
What prevents a miner's block from being accepted across the network if the hash checks out when miner forges transactions in the block?
For example, lets say I'm mining and I want to steal money ...
