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37 Cards in this Set
- Front
- Back
- 3rd side (hint)
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ch9 Bitcoin Core uses _ database |
Google's Level DB |
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Ch9 Each block has _ parent(s) |
1 |
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Ch9 After_ blocks there is so much stability that the coinbase tx can be spent |
100 |
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Ch9 a block is a container data structure that aggregates _ for inclusion in the public ledger |
Transactions |
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ch9 Header size in bytes |
80 |
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Ch9 Structure of a block |
4 bytes block size 80 bytes block Header 1-9 bytes tx counter variable - tx |
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ch9 3 sets of data in block header are: |
previous block, mining competition, merkle tree |
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Ch9 hash block id size in bytes |
32 bytes |
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Ch9 block id can be height. Its not unique when |
Blocks compete |
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Ch9 genesis block has _ transactions |
1 |
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Ch9 every node starts with a blockchain of at least _ block |
1 |
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Ch9 what is a merkle tree |
A data structure for efficiently summarizing and verifying the integrity of large sets of data |
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Ch9 what is the hash algorithm used in merkle trees |
Double sha256 |
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Ch9 To prove a tx is included in a block a node needs to produce _ hashes |
log base2 of (N) where N is the number of tx in the block |
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Ch9 Bitcoin test nets |
segnet, regtest , testnet |
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ch9 Bitcoin network created by Satoshi Nakamoto |
mainnet |
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Ch10 in 2017 miners income was _ % fees |
0.5 |
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Ch10 first 4 years each block contained _ bitcoins |
50 |
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Ch10 after _ million blocks, mining blocks will contain no bitcoin |
21 million |
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Ch10 consesus in bitcoin happens overtime as nodes select longer chain. This kind of consensus is called: |
Emergent consensus |
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Ch10 nodes check this in each tx to consider it valid. (List 3) |
Sintax structure Inputs n outputs not empty Tx size nLocktime Unlocking script |
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Ch10 what does the mempool stores |
independently verified tx |
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Ch10 first tx in a block is called |
coinbase transaction |
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ch10 coin base rewards half every _ blocks |
210 000 |
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ch10 fields in the block header |
version previous block hash merkle root Timestamp Target Nonce |
6 |
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Ch10 mining is hashing repeatedly the _ changing the _ parameter. Unitil hash matches a target |
Block header, nonce parameter |
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Ch10 notation of 8 bits for mining target is called |
target bits |
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ch10 difficulty attempts to keep mining time to _ min |
10 |
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Ch10 Difficulty changes every _ blocks |
2016 |
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Ch10 there is max factor of _ by which difficul ty increases |
4 |
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Ch10 criteria (list) to check block validity (3) |
block Structure is Sintactally valid enforce proof of work timestamp less than two hours in the Future block size acceptable limits Coinbase tx All transactions are valid |
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ch10 a node stores three sets of blocks named |
mainblock chain secondary chain orphan blocks |
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ch10 protocols for pool mining (2) |
Stratum, GBT ( get Block Template) |
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ch10 critisism of soft forks (3) |
changes are still irreversible validation relaxation technical debt |
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Ch10 mechanism to vote bip number is described in BIP _ |
BIP 9 |
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Ch10 Bip 34 is a replaced proposal for voting. Some problems with BIP34 are (3) |
No way to reject and propose again Only one proposal may be voted at a time reduces the availability of the version field |
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ch10 Percentage of blocks that must agree for proposal to be activated |
95 |
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