Bitcoin plummeted to $7,800 in the early hours of this morning. I believe that many small partners who hold coins are almost frustrated.
It’s okay. Although Bitcoin is always worn down when you are not watching the market, you can calm down and find something else to do. For example, you can take a look at the decrease in the number of Bitcoins. What role does the Bitcoin block size limit play out of it? What does the change in block size mean?
The scalability of Bitcoin has always been a big problem. One of the important reasons is that the block size of the Bitcoin limits the upper limit of the transaction volume. You may ask, it is enough to increase the block size, why is the block size? Can’t more be better?
Don’t say, the size of the block is really not determined by a single shot, there are many doorways inside. A few days ago, a bunch of netizens tore away this issue. What is the point of the block size limit? Why did they tear them up again? Let us find out in the article.
What is the Bitcoin block size limit?
The Bitcoin block size limit is an important parameter in the Bitcoin protocol. It determines the size of the Bitcoin block and thus determines the number of transactions that can be confirmed on the Bitcoin blockchain within a 10-minute block interval.
Satoshi Nakamoto did not mention this parameter in the Bitcoin white paper, but later when he led the development of the Bitcoin project, he chose the block size limit as 1MB. The conversion is what we often say that Bitcoin can process seven per second. Transactions. However, in real scenarios, the size of the space occupied by each transaction is different, so the number of transactions processed by Bitcoin per second fluctuates between three to seven.
In 2017, Bitcoin’s block size limit was replaced by a block weight limit, and the accompanying standard became 4 million “weight units”. This greatly changes the “charging strategy” of data in the blockchain: some data is heavier than others. The more important point is that this greatly increases the block size limit: under the new standard, the theoretical size of a Bitcoin block can reach 4MB, and in practice, the maximum size can reach 2MB. The specific size depends on the block size. The type of transaction included.
Why do people disagree about the block size limit?
People have different opinions on the block size limit. The fundamental reason is that no one can tell whether this limit is part of the Bitcoin protocol. If it must be the Bitcoin protocol, how big should it be?
Satoshi Nakamoto never publicly explained why he added a block size limit to the Bitcoin protocol. Presumably, he intended to use the block size limit as an anti-spam measure to prevent attackers from making a large number of fake Bitcoin transactions and overloading the Bitcoin network. There are also some speculations that Satoshi Nakamoto intended to use the block size limit as a temporary measure, but it is not clear whether Satoshi Nakamoto intended to pass the transition period for a long period of time or to stop using it after meeting certain conditions. But from the code point of view, the block size limit does not seem to be a temporary transition.
Several years after Satoshi Nakamoto left the Bitcoin development team, developers and users began to doubt the necessity of block size restrictions. As the number of Bitcoin users grows, some people believe that it is time to increase or even remove the block size limit to avoid future Bitcoin blocks being filled with transactions, which will make the Bitcoin network congested. Others believe that the block size limit is an important security parameter in the Bitcoin protocol, so it should not be erased, at least it should be removed more conservatively. Some people think that 1MB prescribed by Satoshi Nakamoto is actually too large, and therefore advocate that the block size limit should be reduced.
And because Bitcoin is decentralized, this makes the problem more complicated. No organization or individual can decide whether the block size limit of Bitcoin should be increased or decreased. Due to the interests involved, whether Bitcoin’s block size limit should be changed, how to make this decision, and who makes this decision, these issues caused by the change of Bitcoin block size limit have caused huge controversy. It even exceeds the Bitcoin block size limit itself. In this article, we will focus on the views of all parties, and we will not discuss too much about right and wrong.
Why can’t Bitcoin blocks be too small?
Please note: The industry has a lot of controversy about the Bitcoin block size limit. Some people think that the block size limit is too large, and some people think that the block size limit is too small. In this article, we only introduce those commonly recognized views.
If the Bitcoin block is too small, the number of transactions that the Bitcoin network can handle will be limited. Those who support increasing the block size of Bitcoin believe that a block that is too small will cause two serious problems.
1. The blockchain lacks enough space
First of all, the small Bitcoin block size means that the blockchain does not have enough space to accommodate user-initiated transactions, so there must be some transactions that cannot be confirmed for a long time. In order to compete for the limited block space, users have to bid on the transaction fees of the blockchain to urge miners to prioritize their transactions. If this phenomenon is not controlled, a large number of users will escape Bitcoin. So in the future, there will only be institutions similar to banks in the Bitcoin blockchain to conduct transactions, and ordinary users who want to conduct transactions can only open accounts with these institutions. In other words, this will be in the blockchain world. Opening the door to some reserve banking, transaction review, and some traditional financial issues in China goes far against the vision of Bitcoin.
2. Reduce the competitiveness of Bitcoin
Those who support the increase of Bitcoin block size believe that too small a Bitcoin block size will bring about a very urgent problem, which is to reduce the competitiveness of Bitcoin. If the block size is too small and affects the user’s experience, over time users will switch to other competitive cryptocurrencies, or even abandon the advanced technology of blockchain.
Why can’t Bitcoin blocks be too big?
Please note: The industry has a lot of controversy about the Bitcoin block size limit. Some people think that the block size limit is too large, and some people think that the block size limit is too small. In this article, we only introduce those commonly recognized views.
Those who oppose increasing the block size of Bitcoin believe that if the block is too large, there are roughly three risks, and these three risks accurately contain many small risk items.
1. The cost of operating Bitcoin nodes has increased greatly
The first risk of increasing the block size is that doing so greatly increases the cost of operating nodes for Bitcoin miners. The increase in cost mainly comes from the following four aspects :
- Increase the cost of storing blockchain data, because doing so will make the amount of blockchain data grow faster.
- Increase the bandwidth cost of uploading and downloading all transaction information and block information.
- Increased the CPU calculation cost required to verify all transaction information and block information.
- The larger the blockchain, the more time it takes for a new node to join the blockchain network because the new node must download and verify all past transactions and blocks.
If the cost of operating a Bitcoin node is too high, users may (or have to) choose a lightweight Bitcoin node, so they will not be able to verify whether the transactions they receive are valid.
For example, an attacker may send bitcoins fabricated out of thin air to users who use these lightweight nodes. Because these users do not know all the transaction records in the bitcoin blockchain, they cannot distinguish whether the transaction is effective. In this case, users will only realize that they have been created by a fake transaction when they use the bitcoin but cannot spend it. You may question how the attacker’s transaction has been added to the block. It is invalid because some miners colluded with the attackers.
If over time, most users run such lightweight nodes that cannot immediately identify whether the transaction is valid, or even impossible to identify at all, this will bring great risks to the Bitcoin ecosystem. Because in this case, the Bitcoin protocol is likely to be kidnapped by miners. Due to the large-scale use of lightweight nodes, the number of miners is gradually reduced, and their supervision will also decrease. Miners can generate bits at will Currency, or spend Bitcoin that is not yours. Therefore, only a healthy blockchain ecosystem with a large number of users and users verifying their transactions can ensure the security of the blockchain.
In the Bitcoin white paper, Satoshi Nakamoto admitted that there would be such a problem and suggested a technical solution called “fraud proofs” to ensure the security of lightweight clients. Unfortunately, Satoshi Nakamoto did not elaborate on the exact meaning of the fraud-proof technology. So far, no one has been able to figure out what the fraud-proof is all about. In fact, some Bitcoin developers currently do not even It is believed that fraud-proof technology is feasible.
2. Mining becomes centralized
The second risk of increasing the block size is that doing so may lead to centralized mining. According to the setting of the blockchain protocol, whenever a miner finds a new block, it will send this block to other miners in the blockchain network. Under normal circumstances, larger blocks take longer to propagate to other miners on the network. In other words, larger blocks have longer delays. However, one thing that the blockchain protocol does not mention is that the miner who finds the block can immediately start mining the next block on its basis, which will put him in the lead when looking for the next block.
Miners (or pools) with greater computing power are more likely to be able to dig blocks than miners (or pools) with less computing power, and the more blocks they dig, the better their leading position More, this means that miners (or pools) with more computing power tend to have more advantages, and will eventually phase out those miners (or pools) with less computing power, thus forming a more centralized mining ecosystem. If the mining process is too centralized, some miners may eventually occupy 51% of the entire network’s computing power, thus having the capital to attack the blockchain network.
This may be the most complicated and detailed argument put forward by the party as opposed to increasing the block size of Bitcoin. However, even miners with more computing power have the motivation to create larger blocks (because block delays can make They benefit from the first opportunity of the next round of mining), but if the block they dig has a large delay in spreading to the entire blockchain network, then this delay may also cause them to suffer losses. For example, when this block is being propagated, a block dug by another miner spreads across the entire blockchain network with a smaller delay, and then other miners will start the next round of mining on that block Mine, so that the miner’s previous block is likely to be invalidated, and the next block is in a disadvantaged position. It can be said that he lost his wife and broke down. There are many technical solutions that can alleviate these delays, such as some technical solutions to prevent damage caused by centralized mining, but these solutions are more or less compromised.
3. Lower mining subsidies may affect the security of the network
The third risk of increasing the block size is that doing so will greatly reduce the user’s transaction fees. In the case of limited block space, users must increase the transaction fee to ensure that their transaction is added to the block by miners, and as Bitcoin’s block mining subsidy continues to be cut, the transaction fee will become Bitcoin An important part of mining rewards, and Bitcoin mining rewards are the core of the Bitcoin security model. If there is no block size limit, transaction costs will be severely reduced, mining rewards will become less and less attractive, and the security of the blockchain will become less and less guaranteed.
You may ask: Why are transaction fees shrinking? This is because even though individual miners still insist on processing only those transactions whose fees exceed the minimum transaction fee standard, other miners are likely to deal with those transactions with very low transaction fees in a stronger attitude than none so that the miners get transaction fees over time The reward will get lower and lower.
Careful, you may have noticed that the party who supports the increase in the size of the Bitcoin block and the party who opposes the increase in the size of the Bitcoin block are both making a fuss about the impact on transaction costs . The supporting party believes that the high transaction fee will reduce the bitcoin. The attractiveness of Bitcoin and the opposing party believes that lower transaction fees will affect the security of Bitcoin.
Bitcoin core developers
Will the block size limit be increased?
Bitcoin Core developers dominate (but do not fully control) the Bitcoin implementation used by the current Bitcoin network. Therefore, many users who support increasing the block size of Bitcoin have always hoped that Bitcoin core developers want them to increase the block size limit in the implementation of Bitcoin.
Bitcoin Core developers lived up to expectations and did increase the block size limit, but it was achieved through an upgrade of the Segregated Witness (SegWit) protocol. In the Segregated Witness protocol, the block size limit is replaced by the block weight limit. Under this standard, the theoretical size of a Bitcoin block can reach 4MB, and in practice, the maximum can reach 2MB. The specific size depends on the block. The type of transaction included. A very clever point is that this is a backward-compatible soft fork protocol upgrade, which means that users can choose this update without tearing the Bitcoin network.
However, because Bitcoin Core developers chose a soft fork instead of the hard fork recommended by many users who support increasing the block size of Bitcoin, many users do not agree that this is an increase in block size. Size limit moves.
In fact, the reason why Bitcoin Core developers did not increase the block size limit through a hard fork, they chose a backward-compatible protocol upgrade. This is because a hard fork requires the consensus of all Bitcoin users, otherwise the Bitcoin network may be torn into two parts: a version of Bitcoin that maintains the current block weight limit and one that increases the block size/weight Limited Bitcoin version. At this time, users who maintain the current block weight limit of the Bitcoin version may not think that the other forked version is “Bitcoin”, and users may call it “Bitcoin Core Coin (because it was developed by Bitcoin Core) Personnel to promote ingredients)” or similar names.
Perhaps more importantly, the current Bitcoin Core developer team does not seem to be interested in determining the protocol rules for Bitcoin, nor do they want to split the Bitcoin network. Therefore, when Bitcoin’s user community does not reach a broad consensus on the upgrade of a certain protocol (block size limit or other), they are unlikely to deploy a hard fork. Given that the current users are full of disputes about the block size/weight, this consensus is difficult to form in a short time, but it is likely to happen at the right time in the future.
Alternative solution
In order to increase the block size limit, the industry also provides some alternative solutions. For example, the extension blocks released by the Bcoin team, and some solutions that can achieve similar functions, such as the side chain solution called “big block”, but it is still It is not clear whether these solutions can take up the important task of increasing the block size in a short period of time, but the current industry’s focus seems to be on second-layer scalability solutions like the Lightning Network.
Discussion on Bitcoin block size limit
Has it been censored?
I can give you a short answer, no.
The slightly longer answer is that when users are arguing about the Bitcoin size limit, one of the most popular Bitcoin discussion platforms on the Internet, the Bitcoin sub-section of the social news site Reddit, has added strict review measures. Of course, this review measure is to prevent forum users from forcing software that breaks the consensus agreement before more professional users reach a consensus on the future direction.
At the time, many people did not realize that using such software might lead to the tearing of the Bitcoin network (non-backward compatible hard fork), and publicity always gave people a feeling that Bitcoin is impossible to fork. Therefore, under the premise of not directly promoting software that destroys the consensus protocol, discussions on whether the Bitcoin block size should be increased and whether a hard fork should be carried out in the forum are allowed.
This kind of review measure may be regarded as a “review measure” in the eyes of bystanders, but it is certain that anyone who does not agree with this policy can freely initiate or participate in a confrontation with the Reddit Bitcoin sub-section. It was the situation at the time, and because of this, the Reddit Bitcoin sub-section became the favorite discussion platform for those who like to discuss hard forks and increase the block size limit.
In addition, Reddit is only a relatively small part of the Internet, and it is not worth mentioning in front of the entire world. Although platforms such as Bitcointalk (literally translated as Bitcoin discussion) forums and Bitcoin development mailing lists have been accused of carrying out similar censorship, it cannot be denied that everyone is also vying for enthusiasm on social media, news sites, and conferences. Anyone who is interested in listening to different arguments can freely join the discussion, and those who don’t care about this issue can hardly escape this tit-for-tat argument.
Finally, since those users who support increasing the block size through hard forks have not convinced enough users to support themselves with sufficiently convincing analysis and cases, it seems that some enthusiastic users feel this deep frustration. Transformed into anger towards certain forums and moderators.
What is Bitcoin Cash?
And what is the Bitcoin of Satoshi Nakamoto’s vision?
When it is clarified that Bitcoin core developers will use the Segregated Witness soft fork protocol to update the block size limit (of course, the block size limit is only part of it), some users who support increasing the Bitcoin block size limit, Even knowing that they will be a minority and will fork a new Bitcoin network and new cryptocurrency, they still choose to actively promote a hard fork to increase the block size limit. This new network and the resulting new cryptocurrency is Bitcoin Cash.
Since Bitcoin hard-forked Bitcoin Cash, Bitcoin has implemented several hard-fork upgrades, some of which have forked new Bitcoin networks and new cryptocurrencies.
Among them, the most notable is the Bitcoin SV (Bitcoin Satoshi Vision) of Satoshi Nakamoto’s vision. The Bitcoin of Satoshi Nakamoto’s vision is loosely surrounded by Craig Wright, a man who claims to be Satoshi Nakamoto. It is determined that Craig Wright is not Satoshi Nakamoto himself, so people affectionately call him Satoshi Aomoto (because he is Australian).
Satoshi Nakamoto’s vision of Bitcoin has a larger block size limit than Bitcoin Cash. You are not mistaken, it is 128MB. This is because Satoshi Aomoto believes that there should be no upper limit on the block size of Bitcoin, so this number will still be in the future. It may expand.
