G. Maxwell
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Can someone please explain FIBRE to me like I'm 5 and why is it useful?
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25 votes

First the "why it matters": Fibre (Fast Internet Bitcoin Relay Engine) is a protocol which attempts to deliver Bitcoin blocks around the world with delays as close to the physical limits as ...

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Version in transaction
5 votes

Other transaction version numbers are for future consensus rules. If you create transactions using undefined versions numbers they may be invalidated by future consensus rules, or their outputs may be ...

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What are the downsides to enabling potentially suboptimal or unused opcodes in a future soft fork?
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9 votes

Every piece of additional consensus logic has implementation and ongoing maintenance cost which is perpetual and can never be removed without potentially confiscating some user's assets. When Satoshi ...

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Miner transaction selection - how are sigops considered?
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5 votes

For the purpose of mining transaction selection Bitcoin Core converts sigops into an effective weight value based on the ratio of the limits. If the weight implied by the sigops count is higher than ...

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Segfault when clearing mempool. What am I doing wrong?
5 votes

The only place clear is used on the mempool is after all peers are down. Presumably there are references to it that you can't just leave dangling. See CTxMemPool::Expire in txmempool.cpp for how ...

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Why hasn't cold storage (offline signing) been supported by Bitcoin Core (GUI) up till now (0.19.0.1)?
2 votes

Prior to segwit doing this securely required carrying around enormous prior transactions. Prior to PBST there wasn't a standard serialization that covered all the interesting use-cases. It's been ...

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Is there a way to allow use of unconfirmed RBF outputs in transaction building?
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4 votes

Bitcoin Core will happily spend RBF marked inputs it doesn't avoid them much less prohibit them. Perhaps you're being confused by the fact that it will not spend an unconfirmed input created by a ...

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Including transactions in a block - rules and time / technical aspect
2 votes

There really isn't any "starting over" in mining, because mining is effectively progress free, like a lottery and unlike a race. Nothing is lost when updating the transaction list, other then the ...

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How to calculate the risk-free rate of cryptocurrencies?
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2 votes

Bitcoin itself has no returns: 1 Bitcoin is worth 1 Bitcoin, always. Presumably you actually want to discuss the returns of a Bitcoin plus ordinary currency pair, such as BTC/USD. In that case you'd ...

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Are nodes that don't accept inbound connections necessarily leechers?
5 votes

An outbound connection is functionally equivalent to an inbound connection except in the respect that you initiated it. An outbound only node provides the same resources to the network except that it ...

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51% attack - apparently very easy? refering to CZ's "rollback btc chain" - How to make sure such corruptible scenario can never happen so easily?
10 votes

(adding some color) Some discussion I saw suggested that people promoting this believed they only needed to achieve >50% hashpower, which caused them to overestimate the feasibility. Reorging with ...

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Is there a maximum fee per byte in satoshis?
1 votes

At the moment no more than 17662867.32455670 BTC exist. A transaction can't be smaller than 63 bytes so the "maximum feerate" would be 28036297340566.19 satoshi per byte and increasing with each block....

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Does parent also pay for child?
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2 votes

Does it also work the other way - that is, does transaction with high fee pays for child transaction that has low fees, given that they are both in the mempool? Or is the policy only "one way", from ...

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"HTLCs don't work for micropayments"?
8 votes

A very low value output in Bitcoin (or any similar system) has zero actual value because the cost in fees to spend it would be equal to or greater than the coins it provides. Like someone writing you ...

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Known cases of miners withholding blocks when used as randomness?
3 votes

You're probably better off going to some ethereum venue, as ethereum has been rife with broken schemes like this-- riggable "fair" lotteries and such.

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The order of the generator point G used in bitcoin
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4 votes

It's easy to verify the order (n): Multiply G by n and find that you get the point at infinity. This proves that n is either the order or a multiple of it. Then convince yourself n is prime using a ...

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How many wallets don't support address reuse? (for refunds)
5 votes

I think it would be helpful for you to identify your service here, so that I can encourage people to not do business with you. Users generally have no idea if this will work safely or not, so a ...

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What is the reasoning behind the choice of 2^256-2^32-977 for the prime on the secp256k1 curve?
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11 votes

Secp256k1 was designed to be a 256-bit size elliptic curve without cofactor and admitting an efficient endomorphism for optimization purposes. The choices of the relevant parameters are derived from ...

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Is "Ring Signature" used in "Confidential Transactions" of the Bitcoin?
0 votes

Bitcoin does not have confidential transactions.

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sendtoaddress command doesn't work with bech32 bitcoin core 0.17
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3 votes

It sounds like you are using the wrong address type for the network that you are on. Regtest bech32 addresses begin with "bcrt".

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Confirming transactions in the Merkle root and SegWit
2 votes

But how would someone know which associated transaction is required to hash with your transaction to confirm its validity? And where would you get it from? Your question is a little vague, it sounds ...

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Byzantine Fault Tolerance Threshold of Bitcoin: 1/2 or 1/3? (Edited)
6 votes

It depends on what you're actually asking. Bitcoin doesn't exist within the normal model of BFT consensus so in one sense the answer is mu. Under conventional assumptions Bitcoin will converge on a ...

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Why are exactly 4 bit windows used in the lookup table of libsecp256k1 to speed up point multiplications?
2 votes

What you are talking about is the table used for constant time operations w/ secret values, e.g. for signing and key generation (see the heading "Point multiplication for signing"). To prevent ...

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If I was developing a Bitcoin wallet, should I support both legacy and compatibility addresses?
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5 votes

Displaying two would be justified if you were asking about a BC1 p2wpkh vs a 3xxx p2sh(p2wpkh) because not everything supports BC1 but its pretty good to use when supported. Displaying two isn't ...

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Spending UTXO from same block
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5 votes

The order must be causal. Most blocks today have outputs that were created earlier in the block.

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How secure is using TOR in Lightning Network?
5 votes

The paper you link to when used as advice rather than a scholarly investigation into the tradeoffs of different choices is outright bad advice. The attacks they give are largely generic and have ...

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Can a Bitcoin (secp256k1) key be converted to a Ed25519 (Tor v3) key?
1 votes

The bitcoin key could sign a message containing the onion address. There are several other alternatives but there isn't any way to do this without the key holder producing a message of some kind.

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What will happen if all bitcoin nodes are pruned?
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2 votes

If all nodes were pruned a new node would keep making connections looking for an unpruned peer forever and fail to sync. If instead almost all were pruned it would simply take a longer time than ...

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Bitcoin automatically diverted to bech32 address
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21 votes

I'm sorry to be the bearer of bad news: It looks like your funds are gone and the security of your computer is compromised. A quick google suggests that is one of the electrum phishing destination ...

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How to confirm how many peers a node has?
6 votes

When a node requests one of it's neighbours for a list of it's peers, that node responds with a list of all of it's neighbours. No it doesn't. It responds with list of nodes that its aware of being ...

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