الفهرس 
CHAPTER 1 : INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Bitcoin is a popular cryptocurrency that records all transactions in a distributed
append-only public ledger called blockchain. The security of Bitcoin heavily relies on
the incentive compatible proof-of-work (PoW) based distributed consensus protocol,
which is run by network nodes called miners. In exchange for the incentive, the
miners are expected to honestly maintain the blockchain. Since its launch in 2009,
Bitcoin economy has grown at an enormous rate. This exponential growth in the
market value of Bitcoin motivates adversaries to exploit weaknesses for profit, and
researchers to discover new vulnerabilities in the system, propose countermeasures,
and predict upcoming trends.
Bitcoin is based on peer-to-peer (P2P) network and a probabilistic distributed
consensus protocol. In Bitcoin, electronic payments are done by generating
transactions that transfer bitcoins among users. The destination address (also called
Bitcoin address) is generated by performing a series of irreversible cryptographic
hashing operations on the user’s public key. In Bitcoin, a user can have multiple
addresses by generating multiple public keys and these addresses could be associated
with one or more of her wallets. The private key of the user is required to spend the
owned bitcoins in the form of digitally signed transactions. Using the hash of the
public key as a receiving address provides the users a certain degree of anonymity,
and it is recommended the practice to use different Bitcoin address for each receiving
transaction.
In Bitcoin, transactions are processed to verify their integrity, authenticity, and
correctness by a group of resourceful network nodes called “Miners”. In particular,
instead of mining a single transaction, the miners bundle a number of transactions that
are waiting for the network to get processed in a single unit called “block”. The miner
advertises a block in the whole network as soon as it completes its processing (or
validation) in order to claim the mining reward. This block is then verified by the
majority of miners in the network before it is successfully added in a distributed