Vitalik Buterin Express , adopt Rollup Can be 90% The data and 99% The calculation is under the chain , And then 10% The data and 1% It's on the chain , So scalability can increase by about 100 times . and Rollups and sharding Combined, it will achieve 10,000 Times of capacity expansion .
Original title ： dialogue Vitalik Buterin： Slice and Rollups The combination of the two will bring 10,000 Times of capacity expansion
source ：Lex Fridman Podcast
edit ： The south wind
lately , Co founder of Ethereum Vitalik Buterin Participated in the blog host Lex Fridman In the interview , I talked about cryptocurrency in the interview 、 regulatory 、MEV ( Miners can extract value )、 The etheric fang 2.0、PoS Security 、Layer 2 (Rollups)、 Big mergers 、Polygon And so on . The interview was about 3 Hours , This article is compiled from some of the contents of this interview , Please refer to this interview video for complete content . The following is part of this interview ：
Lex Fridman：Shiba Inu On 2020 Created in , Imitated Dogecoin, You are given... Of the total supply 50% Of Shiba, And then you “ The destruction ” I got the gift 90%, value 67 Billion dollars , And you will 10% ( Value at that time 12 Billion dollars ) To India COVID-19 The rescue fund (Indian COVID-19 Relief Fund), I don't want to have so much power .
Vitalik： Let me first talk about the background of these coins and the story of giving them to me .Dogecoin Initially in 2014 In the year or so, with a kind of “joke” The form is created , People didn't take it seriously at first . I am here 2016 I invested in value in 2000 25000 The dollar Doge, At that time, I was still thinking about how to explain to my mother that I invested my money in these dog coins , The only interesting thing about this coin is that it has a dog logo, It turned out to be one of my best investments . And then in 2020 end of the year ,Elon Musk Start to talk about Degecoin, Then its market value soared to 500 Billion dollars , It has skyrocketed many times , For example, the first time from 0.8 The cent went up to about 7 cents , This is 1 It happened in a few days . I remember when I was in Singapore , See its price skyrocketing more than 100%, And then I thought about what I had Dege It's worth a lot of money , Then I sold half of my holdings Doge, To obtain the 430 Ten thousand dollars and donated it directly . In a few hours , The price goes from about 7 The cent fell to 4 cents . So I sold at the top Doge, At that time, I thought I was a very powerful trader. later Doge Again from 4 The cent went up to 7 And then 50 cents .Doge It's a big influence , Many people who have never heard of Ethereum have heard of Doge. This is something I didn't expect .
And then some people think , since Doge The market value of the company can reach 500 Billion dollars , So you should be able to imitate it for billions of dollars , I think that's creation Shiba These people's ideas . But they gave it directly to me 50% Of Shiba Supply , But they're not the first to give me coins . Around the 2020 end of the year , There's a Oracle project Tellor, I think this project should be Chainlink competitors , I remember they put value directly 50,000 I was called in dollars , And then they went around saying “ see ！Vitalik Holding our Token, He's one of our supporters .” After realizing this , I'll go through it publicly Uniswap Sold their Token, Put an end to this rumor .
then Shiba These people are also smarter , They didn't type money into my address , Instead, I punched the coin into my cold wallet . And then I noticed a lot of people talking about this coin , The money I've been donated is worth billions of dollars , And then after I got my cold Wallet Key , They started selling some coins and donating some directly to several charities . I actually sold 80% Of Shiba And will get ETH To some organizations , And then donated it directly 20% Of Shiba, Including India COVID Rescue funds and other agencies .
Lex Fridman： How do you view the regulation of blockchain ？ What's the best and the worst ？
Vitalik： The best situation is , Blockchain continues to flourish , Then we found a way to extend the blockchain , So people can do all kinds of things on the blockchain , That's all the incredible things that people have been talking about , Then there are many good applications running on the blockchain , For example, people can interact in a better way DAOs、 So that artists can benefit better and so on , And get enough public support , Let people realize that cryptocurrency can do a lot of good things , There are other potential innovations that need to be understood .
The worst case scenario is , People suddenly think that this technology is being used by some bad people Use , But I don't think the government can stop blockchain , But they have the ability to marginalize it , For example, banning all exchanges and all mainstream employers from accepting and using cryptocurrency payments , Make it less influential . Obviously I want something good to happen .
Lex Fridman： Let's talk about Ethereum 2.0.Eth2 How to make Ethereum more scalable 、 Safer and more sustainable ？
Vitalik： In fact, recently we're not emphasizing Eth2 This title , The reason behind this is that at first we conceived a very big vision of Hongwei , Thinking that all good things will happen at the same time ： A brand new blockchain and a brand new protocol . Later, we slowly adjusted the road map to a more gradual form ,PoS And slicing (sharding) It all happened over time , So are all the functions and features , Although ordinary Ethereum users feel seamless experience , It may be more complicated than the previous hard fork upgrade , But it's not that complicated from the user's point of view .
Once thought of as Ethereum 2.0 Two flagship features of , And now it's just considered the flagship function of the next Ethereum evolution , Namely PoS And slicing (sharding).PoS It's a consensus algorithm or consensus mechanism , Consensus mechanism is the way in which network nodes link in what order for which block or transaction , Make sure that once a block is on the chain, it can no longer be reversed .
The existing blockchains such as bitcoin and Ethereum use PoW, Basically, there are many computers in this network ( node ) Reach a consensus on which block to accept , And sometimes two blocks are released at the same time , Therefore, it is necessary to reach a consensus on the sequence of blocks , So we need a kind of “voting game”( The voting game ). But who has more voting power can't pass “ One person one vote ” The way of , Because of some bad guy There may be... On its computer 1 00 100 million virtual computers , So he has 100 100 million virtual nodes , And then you might have 99% And control everything in the network .
To prevent this from happening ,PoW and PoS It's all based on how much you contribute to the network economic resources( Economic resources ) To decide your voting weight proportionally . So in PoW in , You have to prove how much economic resources you have , That's how many computers you have and 24*7 Run them , It does work , Because if you want to attack the network , You need to put in more computers and more money and electricity , The cost is very high .
And in the PoS in , Unlike PoW Through as in 24*7 Contribute your computing power , You just need to pledge some money into the system as economic resources . I like PoS For many years , Because it requires less resources , It is not like PoW That requires buying mining equipment from manufacturers and consuming a lot of energy , and PoS Just run it on a common computer , You can run it on the normal computer you use now PoS Verifier node . So it's less resource intensive , No burden on the environment . Another reason is , be based on PoS, Blockchain doesn't need to be like PoW So pay so much for the people who maintain the network ( The miners ), At present, bitcoin and Ethereum provide about half of the total supply every year 4% To the miners , Ethereum is released about every year 470 ten thousand ETH, The current total supply is 1.15 Billion ETH. But through PoS, We expect the annual increase to be about 50 Wan to 100 ten thousand ETH, This means that the total supply will not increase too fast .
Lex Fridman： You feel PoS How safe is it ？
Vitalik： In my submission PoS It's very safe , Because if you want to attack Ethereum successfully , So basically, you need to have the equivalent of ETH Number , For example, now we have 500 ten thousand ETH Pledged ( In the beacon chain ), And then you ( The attacker ) Need to own 500 ten thousand ETH And join the network , these ETH It's worth about 150 Billion dollars , I think it's more expensive than attacking bitcoin networks ; secondly ,PoS It's better to recover from an attack than PoW More easily , stay PoS We have a lot of measures against attacks in the war , For example, we have automatic slashing ( Forfeiture ) The mechanism will destroy the money pledged by the perpetrator , And communities can respond by coordinating soft forks ( The success of ) attack , The attacker will lose a lot of money in the new chain .
Lex Fridman： Some people think MEV ( Miners can extract value ) This is what Ethereum is facing A threat , What is? MEV And how to deal with it ？
Vitalik：PoW and PoS There will be MEV (Miner Extractable Value) problem , It can also be called Block Proposer Extractable Value (PBEV, That is, block proposer can extract value ). The basic idea is that if you have the ability for which transactions to be packaged into blocks in what order , So you can use this advantage to get economic benefits , It's not just trading fees that make money , For example, to make a profit by running or following other people's trade , It can make the proposer of block get a certain proportion of income .
The reason why this phenomenon is a challenge , Because first of all, it sometimes reduces the user experience , So that the user's transaction is not in a favorable position , And the bigger risk is MEV Economies of scale for miners or verifiers , May lead to PoW Mining or PoS Verification is more centralized . So the ecosystem has been able to MEV Pay attention to , Such as Flashbots And other projects are already underway . It's really a risk , But we're already doing something to deal with .
Lex Fridman： Let's talk about the concept of capacity expansion , To be specific Layer 1、Layer 2 And the interaction between them , And the idea of fragmentation .
Vitalik： There are two paradigms for expanding blockchain , That is to say Layer 1 Extension and Layer 2 Expand .L1 Expansion is to enable the blockchain itself to handle more transactions through some mechanisms , Although the blockchain itself has some performance limitations ;L2 Expansion is just not right L1 To change , Instead, create protocols on the chain to inherit L1 The security of , At the same time, a lot of things are going on under the chain , So you can get more scalability . In Ethereum , The most popular L2 The paradigm is Rollups, The most popular L1 The expansion paradigm is fragmentation (sharding).
Lex Fridman： One way to extend the blockchain is to increase the block size , It's about Sharding Before , Can you talk about the dispute over the size of the block .
Vitalik： This is a better way to write to the blockchain ( That is, trading on the blockchain ) And better read the blockchain ( That is, let the node verify whether the transaction on the chain is correct ) The trade-off between . In terms of decentralization , Both are equally important . If the read cost of a blockchain is high , This means that people need to trust a few nodes , And these nodes can change the rules of the blockchain without the consent of others ; And if the writing of a blockchain ( transaction ) It's very expensive , So everyone will move to a very centralized secondary system .
So I think it needs to strike a balance between the two , Biased to one side will lead to unhealthy development of blockchain . I think the current block size of bitcoin 1 M There are two main reasons , One is that they think it's really important to be able to read blockchains ; The second is that many people are maintaining the principle of no hard bifurcation . A larger block size means that the blockchain will be more centralized , Because fewer people will be able to run nodes , And it can also bring hard bifurcations .
Lex Fridman： So what is fragmentation ？ What are the characteristics of fragmentation ？
Vitalik： Slicing doesn't increase parameters like increasing block size , But to Change the architecture of the blockchain , So that a single node in the network only needs to store part of the data of the whole network and process part of the transactions . The challenge of adopting this model and applying it to blockchain is , Blockchain is not just about distributing data to the network , It's about reaching a consensus on the data that's scattered across the network and making sure that the data that's reached is right . So there's a paradox , For example, suppose you need one that can process every second 10,000 The blockchain of this transaction , But each computer node in the blockchain can only process 100 transaction , So how can a single computer trust other computers without verifying all transactions ？
There are a number of ways to do this , For example, one way is through random shuffling ( Upset ) Verifier , For example, in a PoS There's something in the chain 10,000 A verifier ( Pledgor ), For the sake of simplicity , We assume that each verifier will pledge the same amount of money , Then randomly scramble the verifier , Will the 100 A verifier ( Form a committee ) Assign to verify a block , in addition 100 A verifier is assigned to verify another block , And so on . So the way to broadcast effective information is , some 100 When a verifier verifies a block, he signs it , To show that they agree with the effectiveness of the block , Then all the signatures of the block are aggregated into 1 Sign and broadcast to other verifiers in the network , Then other verifiers just need to verify the signature , Without directly verifying the transactions in the block . When other verifiers see this signature , It's not a direct belief that this block is effective , It is It is believed that most of the verifiers in the block agree that the block is effective . So if I believe that most of the verifiers in the block are honest ( Because these verifiers are randomly assigned , The attacker can't cram all the verifier nodes under his control into the same committee , In other words, the nodes controlled by the attacker will also be randomly disrupted ), Then illegal blocks will not be included in the blockchain . It's a simple form of fragmentation .
There are other, more sensible forms , such as zk-SNARKs The concept of , It's a zero knowledge proof , This is the idea of generating cryptographic proofs , Represents the generation of a proof by running complex operations on a piece of data . If this kind of proof is generated , For example, you see a zk-SNARKs Proof means that a block is valid , Then you can believe that the block is effective . Another method is called data availability sampling (data availability sampling), Make sure that the data in the block has been released . Basically , If you stack these methods , So you can create such a blockchain system , Let individual participants believe that everything that happens on this chain is right , You don't have to verify it yourself . This is it. Sharding.
Lex Fridman： as far as I am concerned , Ethereum is proposed to achieve 64 Strip and slice , This is how to achieve capacity expansion ？ Is the quantity fixed ？ This is to achieve its scalability with credit cards or Visa Compete with each other ？
Vitalik： as time goes on , This 64 The number of slices can be increased by hard branching , And it can be realized in theory 1024 A chain of fragments . More fragmentation chains will bring challenges , For example, there needs to be a logic to check and manage all these pieces , If there are too many pieces, it will bring higher costs , But still, you can improve a little bit . And another thing we're doing , Namely take Sharding And Rollups Combine .
Lex Fridman： Oh ,Rollups. Let's talk about it now L2 Idea ,
Vitalik：Rollup The basic idea of this is , The user sends the transaction to a central aggregator (aggregator), In theory, anyone can be someone Rollup One of them aggregator, It's a model without permission .Aggregator The thing to do is , They will remove all transaction data that has nothing to do with the update status , Then keep the data needed to update the status and compress it , So just publish these little compressed data on the chain , Instead of publishing all the transaction data . The amount of data published on the chain could be reduced tenfold .
And there's no calculation on the chain , It's down the chain . There are two ways to do this , One of them is zk-Rollup, That is to provide a zk-SNARK Proof is used to show “ I calculated , This is my proof of hash calculation ”, The proof is then submitted to the chain , And then everyone goes to verify the proof , Without having to verify all of these transactions ; The other way is Optimistic Rollup, Basically, first of all, someone claims that they think the result of the transaction is correct , Then another person can object and claim that the outcome of the transaction is different , If there are such differences , Then you need to publish the data of the whole block on the chain and verify it , The wrong side will lose a lot of money .
therefore , adopt Rollup Can be 90% The data and 99% The calculation is under the chain , And then 10% The data and 1% It's on the chain , So scalability can increase by about 100 times . Now these systems have been launched for some applications , such as Loopring This is based on zk-Rollup Our payment platform , You put money in Loopring The system can trade at a very low transaction fee , such as 5 cents ( instead of 5 dollar ). Even though the current Ethereum Rollups Only a few applications are supported , But it's expected that in a few months there will be a fully Ethereum compatible Rollups. So it will Rollups and sharding It's a combination of the two 10,000 Times of capacity expansion , Bring thousands of tps.
Lex Fridman： So this kind of scalability can handle a large number of transactions faster , And it's cheaper .