Putting It All Together Understanding Bitcoin Mining Economics and Profitability One of the most exciting features of the Bitcoin network is bitcoin mining. It is the method used to create new bitcoins and to verify network transactions. We'll examine the economicsof Bitcoin mining and how profitability is established in more detail in this article. Mining Economics Mining Bitcoin is an expensive process that requires a significant investment in hardware and electricity. Finding a single block takes computing power equivalent to about 10 to the20 hashes, making it a highly resource-intensive process. Despite this, the block reward isabout 25 Bitcoins, which translates to a significant sum of money. Therefore, the question ofwhether or not it’s profitable for a miner to mine boils down to an economics question. The economics of Bitcoin mining may be simplified down to a simple calculation. The block reward and transaction fees determine the mining reward that the miner will earn. The minermust decide if the reward outweighs the whole cost, which includes the price of theequipment and power. Electricity costs for bitcoin mining are so high that it accounts for asizable chunk of overall costs as opposed to only the initial cost of hardware. Profitability The miner makes money if the returns outweigh the costs. Otherwise, the miner suffers a loss. Unfortunately, there are difficulties with this straightforward equation. First off, hardwarecosts are fixed, whereas electricity costs are variable and accumulate over time. Second, thespeed at which a miner discovers blocks is influenced by both the hardware's power andhow much of the overall global hash rate that power represents. Profitability becomesconsiderably more challenging as a result. Another problem is that while the reward is given in Bitcoins or transaction fees, the cost of mining is expressed in terms of dollars or the miner's chosen currency. Hence, thecalculation depends on the exchange rate of Bitcoin at any particular time. Mining Strategies
Finally, we made the assumption that the miner is genuinely interested in adhering to the protocol. The next block that extends the longest valid branch may not necessarily be thebest option for a miner to choose from. The complexities of the many tactics the miner canuse are not entirely covered by this equation. There are no easy solutions to the challenginggame theory problem of analyzing what is rational for miners to perform. Recap and High-Level Points In summary, Bitcoin mining is an expensive process that requires a significant investment in hardware and electricity. Profitability depends on a simple equation that factors in themining reward, hardware and electricity cost, and the exchange rate of Bitcoin. However,several complications make it even more complicated, including the fact that hardware costis a fixed cost, while electricity cost is a variable cost, and the rate at which a miner findsblocks depends on the power of their hardware as a fraction of the total global hash rate. There are a number of additional aspects to take into account, such as the fact that the cost of mining is expressed in terms of dollars while the reward is expressed in terms ofBitcoins or transaction fees. Furthermore, a variety of mining techniques can be used,making it challenging to choose the most effective strategy. The Bitcoin network is a complex and fascinating system that has many intricacies that must be considered in order to understand it fully. Mining economics and profitability are justa few of the many factors that come into play when mining Bitcoin. Deep Dive into Distributed Consensus and Bootstrapping in Bitcoin Bitcoin is a revolutionary digital currency that operates on a peer-to-peer network. Unlike traditional currencies, Bitcoin is decentralized, and there is no central authority governing it.Instead, it relies on a distributed consensus mechanism that enables users to verifytransactions and maintain the integrity of the network. In this article, we will explore how thenotion of distributed consensus permeates Bitcoin, and how bootstrapping plays a crucialrole in the security of the blockchain. Consensus in Bitcoin In a traditional currency, consensus plays a limited role. We have a consensus process around what is the exchange rate of the currency. This is similar to the concept of consensusin distributed systems, which is also true for Bitcoin. In Bitcoin, we need consensus aroundthe value and exchange rate of the currency. However, consensus goes much deeper inBitcoin than in fiat currencies. In fact, we need consensus around the state, which is whatthe blockchain accomplishes, i.e., a record of which transactions are valid, or whichtransactions have even happened.
Ownership of bitcoins is nothing more than other nodes thinking that a particular user owns a certain number of bitcoins. This is because the sum total of all user addresses recorded inthe blockchain network considers that user as the owner of a certain number of bitcoins. Theultimate nature of truth within Bitcoin is subjective consensus. Rules of the System In addition to consensus around the value and exchange rate of the currency and the state of transactions, we need consensus about the rules of the system. Occasionally, the rules ofthe system have to change. There are things called soft forks and hard forks, which we willdiscuss in detail in later lectures. However, it is essential to ensure that all nodes agree tothe rules of the system. Bootstrapping in Bitcoin Bootstrapping is a fascinating concept that plays a crucial role in the security of the blockchain. It refers to the interplay between three things in Bitcoin: security of theblockchain, a healthy mining ecosystem, and high and stable value of the currency. Each ofthese properties is dependent on the other. At the heart of this interdependence lies the security of the blockchain. For Bitcoin to be a viable currency, the blockchain must be secure. However, what is necessary for theblockchain to be secure? An adversary shouldn't be able to overwhelm the consensusprocess by creating a lot of nodes and taking over 50% or more of the new block creation. A prerequisite for the security of the blockchain is having a healthy mining ecosystem made up of largely honest protocol-following nodes. But what's a prerequisite for that? When canwe be sure that a lot of miners will put a lot of computing power into participating in this hashpuzzle-solving competition? Well, they're only going to do that if the exchange rate of Bitcoinis pretty high. The reason for this is simple. Miners receive rewards denominated in bitcoins, whereas their expenditure is in dollars. Therefore, the more the value of the currency goes up, themore incentivized miners will be. However, what ensures a high and stable value of thecurrency? This can only happen if users in general, i.e., people who want to buy bitcoins,have trust in the security of the blockchain. If they believe that the network could beoverwhelmed at any moment by an attacker, then Bitcoin is not going to have a lot of valueas a currency. Interlocking Interdependence
We have this interlocking interdependence between these three things: security of the blockchain, a healthy mining ecosystem, and high and stable value of the currency. Theexistence of each of these is predicated on the existence of another. At the beginning of Bitcoin's creation, none of these three things existed. First of all, can this attacker steal coins from an existing address? When it comes to stealing coins from an existing address, the answer is no. Unless the attacker can subvert the cryptography, it's not possible to subvert the consensus process. Ifthe attacker creates an invalid block containing an invalid transaction that steals Bitcoinsfrom an existing address, the honest nodes will not accept this block. Instead, they will keepmining based on the last valid block found in the network, creating a fork in the chain. Whenthe attacker tries to send these invalid coins to a merchant, the merchant's honest node willreject the invalid transaction because the signatures did not check out. Therefore, theattacker cannot steal coins from an existing address through a 51% attack. It is worth noting that this is a somewhat hypothetical situation. In reality, if there were signs of a 51% attack, the developers would notice and try to react to it. They would update theBitcoin software and make changes to the P2P network to make the attack more difficult tolaunch. However, for the purpose of this discussion, we are assuming that a 51% attackoccurs without any changes or tweaks to the rules of the system. Now, let's move on to the next question. Can the attacker suppress sometransactions? Let's imagine the attacker doesn't like Carol and wants to stop any coins associated with Carol's addresses from being spent. The attacker has the option to forbid both the creationof new blocks and the addition of new blocks to existing blocks that already containtransactions from Carol's addresses. The broadcast of these transactions to the peer-to-peernetwork cannot be stopped by the attacker. The transactions will still manage to reach thevast majority of nodes because the network is not dependent on the block chain orconsensus, given that the attacker does not completely control it. The peer-to-peer networkwill therefore accept the transactions even if the attacker tries this attack, making thevulnerability obvious. Lastly, can the attacker change the block reward? Changing the block reward corresponds to changing the rules of the system. Similar to stealing coins from an existing address, the attacker cannot do this. Changing the blockreward requires subverting the consensus process, and if the attacker were to do so, thehonest nodes would not accept the new block because it violates the existing rules of thesystem. Therefore, the attacker cannot change the block reward through a 51% attack. In summary, a 51% attack cannot be used to steal coins from an existing address, suppress specific transactions, or change the block reward. While these attacks are notpossible through a 51% attack, the existence of such attacks highlights the importance ofmaintaining a decentralized and secure network. A secure network is not only critical for
ensuring the integrity of the Bitcoin system but also for building trust among users andattracting new users. It is crucial that we keep looking for innovative approaches to fortify the Bitcoin network against future attacks as we go. To protect the integrity of the network, developers and otherstakeholders must continue to be attentive in spotting vulnerabilities and putting newsafeguards in place. By doing this, we can make sure that Bitcoin continues to be a safe anddependable platform for investments and transactions.