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12

In order to be sure that an address balance is correct, you need to check that all the transactions on that address are valid. So in order to generate a list of addresses and balances that you trust, you must first download and verify the entire block chain. Actually, the way Bitcoin works, what you actually need is a list of unspent transaction outputs (...


11

When Bitcoin was invented, Blockchain analysis was not as advanced as it was today and pseudonymous transactions were believed to be closer to anonymous than they are with Bitcoin today. Under the current Bitcoin system, privacy can be greatly improved by avoiding fiat entry/exit ramps connected to your identity and by avoiding reusing BTC addresses. Yes ...


6

It doesn't mean anything for the average Ripple user. In January of 2013, a bug in the Ripple server caused ledger headers to be lost. All data from all running Ripple servers was collected, but it was insufficient to construct the ledgers. The raw transactions still survive, mixed with other transactions and with no information about which transaction went ...


6

Miners do not prove validity. They solve the problem of needing to decide between two potentially conflicting but otherwise valid versions of history. The rule that full nodes follows is that they accept the longest valid block chain, where valid is defined by the network's consensus rules, and long is defined as having more mining work performed. If a ...


6

I know that the blockchain technologie works so well, because everybody has basically a copy of the last ledger. Yes, every full bitcoin node has a copy of the blockchain (aka ledger). Therefore, if a transaction happens, everybody inside the network has to "approve" the transaction to do it. Correct, every transaction is propagated to all bitcoin ...


5

How does a new user realizes which is the correct copy of the ledger to be used when initially updating(downloading) the ledger They find the highest-work valid blockchain. This is not the same thing as the most popular blockchain - if 999 nodes tell your node they're on a chain, but one node tells you about a longer chain, you will prefer the longer chain. ...


5

The ledger has to be public in order for Bitcoin to be decentralized. The designers of Bitcoin didn't want to need anyone to play the role of a "bank" who keeps all the records, and whom everyone else has to trust to do that properly. For instance, when you keep a bank account, you are trusting your bank to keep your money and give it back to you on ...


4

Exactly the same question was asked to a Bitcoin developer (Peter Todd) during the Bitcoin 2013 Conference. You can watch his answer here For those who are too lazy to watch the video the short answer is that they are doing it for security reasons.


4

First of all, it is important to distinguish between multiple things, all of which are often called 'forks'. The existence of two or more competing versions of history. These happen unintentionally in proof-of-work consensus systems when two miners produce a candidate block around the same time. These get resolved automatically. Software projects branching ...


4

Using words to back up wallets is a process described in BIP 39. Basically, the mnemonic is converted into a seed. This seed is then used as the seed to a Heirarchical Deterministic (HD) wallet, as laid out in BIP 32. The seed is used to generate a Master Extended Private Key, from which all other private keys can be generated. The child key generation ...


4

Yes, you can. The transaction will just not be a SegWit transaction, and not receive its benefits (including lower fees for a given confirmation speed).


3

There are two parts to your question: Blocking: Blocking would entail either nodes refusing to relay transactions paying the crooks, or miners not confirming such transactions. Even if the criminal's address is public and unchanging, which is unlikely due to most wallets generating a new address for each payment, it would require a change to Bitcoin's ...


3

A nice article from corda developer, which explain why corda give up simple “account/balance” ledger and use UTXO-like ledger. https://www.corda.net/2016/12/09/rationale-tradeoffs-adopting-utxo-style-model/ The UTXO model has these advantages: Immutable ledger entries gives the usual advantages that a more functional approach brings: it’s easy to do ...


3

you might be interested to know that the bitcoin blockchain can already be used to store arbitrary data. for example the original whitepaper pdf that satoshi wrote explaining how bitcoin works has actually been uploaded to the blockchain. it was done using 948 outputs in a single transaction for a fee of 0.596175 btc ~ US$143.02 at the time i'm writing this. ...


3

Ledger 8470000 in JSON format (without inner nodes) is 115 MB large. You can get it if you issue the "ledger" API call on a rippled that you own - it's an admin-only call, as it takes lots of ressources to assemble it. If you are asking about the size of the databases rippled uses in the backend, these are about 9 GB (ledger headers + validations archive) ~...


3

You're looking for Freenet, a p2p plataform which is only different from your idea in the fact that, to avoid wasting disk space, Freenet deletes old and unpopular content.


3

There are two separate issues. One is initial synchronization assuming you don't know anything. The other is how servers advance the ledger in synch. For initial synch, you monitor the network and watch for signed validations from validators you trust. You check the timestamp on them and if they are current, you can then begin tracking the ledger chain. ...


3

Yes. The blockchain is stored completely on a full node (unless running in pruned mode) , there are mechanisms to prune and only keep relevant data, however pruning also requires you first get the complete blockchain. The size is approx 120 GB as of now. The blockchain is growing every day (rather every 10 mins). Miners most probably have custom solutions ...


3

Find the HD Public key for your wallets: Open the Ledger Wallet Chrome bitcoin app Click your account in the overview, it’s called “My account” by default Click “Account Settings” in the top right corner, under the balance Click “Export” next to “Extended public key” And when you see the QR code pop, you’re ready to begin the next part. You can test the ...


3

From Michał Zabielski's comment: Unfortunately you are out of luck. Never share your word phrase with anyone. If you do, you effectively give access to your money to someone else. If someone asks you about your word phrase (or anything related to private keys) you can be pretty sure that it’s a scam. To clarify, the device's security was not breached. In ...


3

Ledger uses a secure element chip to store the private key. In simplified terms this means that the private key is stored on a special chip that is almost like a small computer with a Operating System with a very strict and well defined interface. This interface is designed to NEVER allow an extraction of the private key except during the creation of the ...


3

Wouldn't it be saver to generate a mnemonic passphrase manually by just taking random words from a lookup table? No, it would not be. This method may even be insecure if you are actually doing it manually. A BIP 39 mnemonic, if generated properly, is secure. It is just as secure if you randomly choose words too. This is because both methods require a ...


3

If LBC is somehow able to guess anyone's private key, regardless of how the private key is normally stored and generated, then yes, they can just spend the coins. All you need is the private key, it does not matter how the key was obtained. Of course this is impossible to do in practice with today's technology. The range of possible private keys is ...


2

The ledger_index is the 256-bit index of a particular entry in the ledger. The ledger's state tree is a hash tree of index/value pairs. Each index is a 256-bit hash of some kind of locator. If the entry is, say, an account root node, the index is a hash of the 160-bit account ID. If the entry is, say, a ripple balance node, the index is a hash of the two ...


2

Nobody will waste his disk space for storing blockchain. Nobody will spend money for mining blocks. It will be very easy and very cheap for dishonest person to "doublespend" such currency.


2

As you already have described, Ripple transactions are based on exchanging IOUs. As such, when you trade bitcoins on the ripple network, you are trading IOUs denominated in Bitcoin owed to you by some party, e.g. BTC owed to you by Bitstamp. Therefore, as long as the transaction is between Ripple users, it is completely off-chain and can be confirmed within ...


2

@amacilin's answer pretty much nailed it. But I wanted to counter a few such assertions /r/Bitcoin often makes about decentralised being better than centralised. Recently someone said something to the effect of "Blockchain based storage/websites is the answer to the centralised server solutions, which have been around forever" The thing is, centralised ...


2

I have a HW.1 too. I purchased mine, so it came with the recovery card. If you have your recovery card, you might be able to contact their support and ask how you could convert your security card's details into the 16 byte key If you can't do this, then use the link you posted previously to generate a random key, and then generate your card. Remember to ...


2

Is it fair to compare the decision body responsible for forking a blockchain as 'escrow officers'? Not really. Escrow officers are generally agreed upon by all of the parties in a transaction, but there's no practical way to find someone that every blockchain user trusts. How can users of the blockchain network dare to the treat the distributed ledger as ...


2

Miners have mempools where they store all transactions they consider to include in future blocks. They don't put transactions they received into their blocks, right away. But they don't put them into their mempool right away, either. The transactions in each miner's mempool are valid and worth the miner's effort (pay at least a certain amount of fee). They ...


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