Cumulative optimism: current and future scaling of Ethereum

Much has been said about how ZK Rollup can be seen as the future of smart smart contracts. And we do not agree. This sentence explains why. It leverages information learned through an open, secure, EVM-enabled L2 chain with hundreds of dapps, hundreds of thousands of users, and millions of apps.

We build Arbitrum with expectation of quality (or) because we believe OR is the best way to meet our customers' real security needs, unreliable based on EVM L2. We chose the most promising ZK because the system has the best performance and the best price, and we will always make the same choice today. If you want to know why, read on.

Michael Johnson - Story Posted to Flickr as Apples and Oranges - No Comparison, CC BY 2.0,

https://commons.wikimedia.org/w/index.php?curid=4289506)

another one! How long is this post?

Yes, this post is long and a bit technical. Getting through the chain is easy, but we need to look at a few details to discuss the tools to deliver these benefits. We want the tech community to understand our point of view.

If you don't want to read the entire article, here's a quick rundown.

People want unreliable channels to provide security features, ensure success, visibility, and speed, and they want low cost and compatibility with existing devices. .

We have looked at how to use this product wisely compared to ZK rollup.

Since ZK's off-chain value is very high, Optimistic can provide the products that users need at low cost.

Because ZK certifications are expensive, their full integration into the ZK protocol may require specialized equipment and / or significant operations, allowing the network to be more efficient in the middle.

The benefits claimed by ZK can also be applied to the best stacking systems, or at the expense of critical safety or efficiency.

The best prospects are beneficial for large operations, because filling in the numbers is cheaper than counting hard data.

start from zero

Let's start with Ethereum. Ethereum users create businesses to provide or interact with smart contracts. There are several ways you can view Ethereum's changes. On the other hand, it can be considered as an opaque material. But if you look at the content, the marketing is more than that; Request a smart contract to collect data, move assets, etc.

During the transition to Ethereum, two important things happened. First, it understands and Ethereum accepts the ordering process. Second, Ethereum makes these changes and counts status updates.

Cumulation: what Optimistic and ZK have in common

Having each Ethereum node to build each business is expensive, and competition is one type of metric that can reduce that load. The completion of the transition was not the completion of Ethereum but a move to Layer 2 ("L2").

But wait. The rollup is guaranteed by Ethereum. This means that even though this is happening on L2, we need Ethereum to ensure the authenticity of the market. So how does Ethereum provide a claim for the stacking policy?

Simply put, the answer is proof. Rollup proves its authenticity for Ethereum using evidence that can verify the authenticity of a business without completing the transaction.

Cumulation: the difference between optimism and ZK

The proof is magic. This allows Ethereum to diagnose the situation without completing the rollup. You may be surprised to see what this evidence looks like and how it is used in practice. That's what makes the whole competition different.

ZK cumulation uses proof of use. ZK trusts both parties to provide cryptographic information they know about the valid chain that ends in a state. This requires the surety to configure the acknowledgment by running the chain to determine how to configure the acknowledgment, and then perform more complex cryptographic tasks. The proof is based on L1 contracts. ZK certification is genuine, and the cost of certification is affordable enough for the Ethereum industry.

A good hope uses another piece of evidence: proof of deception. As the name suggests, the best prospect is to be positive and not need any evidence to release when announcing a new state to Ethereum. Anyone can post a download that contains confirmation that an edit is complete. Other nodes do the same job and can create problems if they disagree with the acknowledgment from the first source. Dispute resolution can resolve the dispute and ensure that the parties win the race. Parties are encouraged to object only to the affidavit and not to discuss inaccuracies, so in normal cases there is no need to make any changes and request proof of information. The entire process is governed by the L1 contract.

Well. Which type of rollup is the best? In the following, we compare ZK and bullish stacks of different dimensions and explain why we think the future is bullish, and bullish stacks like Arbitrum are inherently more scalable.

Optimistic accumulation against ZK: Nqi

Perhaps the most important difference between a bullish rollup and a ZK is the price.

The best expectation is to make the knots contract. For example, if the contract is extended, the nodes are extended.

ZK, on ​​the other hand, is required to develop complex cryptographic proofs that require hundreds or thousands of elliptical curves of value to include additional functions in the certificate. ZK will bear this cost for each order in each contract. The need to create hard evidence for each instruction, rather than performance, is a downside to ZK's cost and downsides.

ZK supporters argue that sometimes only one party needs to produce a certificate, but good intentions need to have more than one foundation. However, if you run a large chain, you will have multiple nodes no matter what proof you use. Chains really need multiple nodes to provide unchanged lists of request events, free up data exchange for users, and deliver data to users they want to transfer money to L1. The security of the best roll-up chain relies on what nodes are already doing: executing transactions and tracking the actual state of the chain.

ZK, on ​​the other hand, has become very expensive to produce expensive elliptical curves. Doing great certifications with ZK requires specialized equipment, a lot of labor, or both, but expensive.

Conclusion: An optimistic stacking system has the uniqueness and importance of a good price.

Optimistic Rollup nrog ZK: EVM compatibility

An important decision for us when using Arbitrum is the relationship with EVM. Arbitrum is fully EVM compatible, has the same RPC interface, and accepts the same bytecode as EVM. In practice, this means that every number written on Ethereum will work on Arbitrum out of the box.

We have been working on open EVM compatible chains (such as testnet) for over a year and have learned how difficult it can be. Compatibility with the top 95% isn't difficult, but it's not really good enough and it takes a lot of work and out-of-the-box product architecture to get good results.

The ZK system works on a variety of relationships. Some see it as an old heritage and encourage people to learn the language.

However, some ZK systems are not compatible. Of course, it's good for developers and users who don't care about relationships.

We haven't pretended that EVM is the ultimate goal all the time. We believe there are many advantages to EVM, given the design value, numbers, and productivity tools that already work with EVM. Think of an Ethereum deployment task that requires writing new numbers in a new language, allowing new security checks and handling multiple bad and bad code bases. However, even for new tasks that have not yet written numbers, EVM integration is beneficial because it allows those tasks to support a pool of numbers, tools, tools. , and the skills available around EVM.

Some ZK projects are working to use the EVM broadcast version, but despite the confusion, there are still no rules that will allow people to enter into EVM contracts during the ZK rollup. . There is a conflict with the existing spare parts. For example, ZK systems claiming EVM compatibility do not comply with the ADDMOD, SMOD, MULMOD, EXP, SELFDESTRUCT, and CREATE2 opcodes, deciding to remove support for XOR, AND, and OR, and not support industry standards. It supports all precompilations and can limit the number of contract calls in the exchange. This appears to be incompatible with the ZK model, which is preferable to ensure that the ZK EVM relationship is provided with the page details rather than all the relationships used by the rollup of quality objects.

It is worth clarifying that there are a few examples of specialized ZK application systems available today (eg Zcash, ZKSync 1.0, loops). In fact, some of these systems work very well. The main difference is that they are only customized and specialized for special applications suitable for ZK applications. What does not exist today is a wide target that can use EVM for ZK exchange in the same way. There are groups that claim to work, but do not have public policy standards or ZK-EVM contract prices. Based on our experience and all the information available to the public, we have decided that they are otherwise expensive.

Conclusion: only Optimistic supports all EVM compatibilities at the lowest cost.

Optimistic cumulation and ZK: visibility and compressibility for non-violent beliefs

One of the main attributes for which we developed Arbitrum was the perception of a lack of trust. Put simply, unconditional trust visibility means that a person can view or receive the content of a channel without support. Above all, this not only means that everyone can see the image of the state, it also means that everyone can see the entire history of the chain (how the state is now achieved). The electronic device allows a person to run a node that supports unchanged requests, stores historical events, and sees all changes without having to rely on the text of the data sources in the middle. The lack of skepticism makes this possible.

To be honest, I want to talk about the fact that some ZK systems have low visibility and don't provide full blockchain functionality. Listen carefully when you hear the word "squeeze." Are you saying they have better string encoding (Arbitrum will be better in the Nitro version and will be better in the future)? Or did you say some data on the chain doesn't exist unless the middle data centers distribute it later?

A ZK certificate only certifies that the witness knows that the chain is valid. Evidence doesn't tell you what a chain is, and even if you have enough information to identify the evidence, you may not have enough information to create a historical chain.

For example, Alice continued to send 1 ETH exchange to Bob and Bob continued to send 1 ETH exchange to Charlie. Later we found evidence that Alice had 1 ETH less than before, Bob's balance had not changed and Charlie had 1 ETH more previously.

But what? Did Alice pay Bob? Is Bob Paying For Charlie? Alice can also pay Charlie directly. It could be Alice burning ETH and Charlie paying someone else. Maybe Diana, not Bob, is the average person. Bob is looking for blockchain proof, but some ZK stacks do not display the chain and cannot tell the difference.

Many smart contracts require more than just knowing the test sites. They need to understand the connections. You have to know what happened and how to get to the end state. A ZK rollup sometimes provides better "compression" than expected, but it masks the data in the chain so that only the evidence proves that it is not a compression. Delete sensitive files. When Doctor ZK said "no need" to publish the information on the chain, what they really said was that the chainsaw could not be guaranteed. Putting on a visual recognition channel isn't the impact we want.

Conclusion: Excellent performance delivers unmatched reliability at a lower cost.

Optimistic rollup and ZK: unreliable closed synchronization

An important requirement when deciding on a reversal is whether it is credible, with the end result occurring in a timely manner. Simply put, this means that after submitting a trade, you and others should be informed quickly and in confidence of the outcome of the trade, and no one should replace or delete.

The best way to do this is to decouple the order from the business. Sort develops the final market demand system and completes the attempt to complete the product market in this segment. If the success of the market is a decision, such as a decision, the decision in execution is sufficient to confirm the result. Indeed, the result is a functional decision of continuous rotation. If everyone knew the company's decision, anyone could easily decide the outcome.

In order to achieve a temporary finish, the system must be advertised on an L1 channel with enough information for anyone to go straight to the market to know the result with unreliable reliability. . The best run-up would be to print as many link files as possible on the L1 channel.

On a positive note, the advertised costs for the L1 channel are minimal. In fact, Arbitrum typically broadcasts data exchange changes on the L1 channel every minute or so, providing users with a quick result and ensuring that no one can undo it. industry. The best results of the new results were confirmed almost hourly, but the final result was not delayed as completion and completion were decisive.

Generally, the ZK system can work in the same way. However, the ZK rollup which works like this requires the data to be printed from the root and relies on the process to be printed on string L1 and cannot be used (called) "compression" the process is described above . For this "squeeze" process to work, when a batch of L2 transactions is published, the L2 transactions must be acknowledged in real time in the same L1 track.

So if you want to use the touted "squeeze" process, you have two options for ZK rollup.

Regularly report operations and run certifications every minute or so. This maintains speed, but ZK-Proof should be generated from the chain every minute and identified on the L1 chain. Depending on the application, the cost of ZK certification is estimated at 500,000 and 5 million fuels.

Amendments and certificates are sent every hour: this makes the cost of the ZK proof check interesting, but the deadline is extended to one hour. During the interval between when the user sends an exchange to the ZK operator and when it is placed on the chain, the user only trusts the operator because the message does not guarantee that the exchange will be included.

If you are building a ZK system, you will find that these two options are not necessary. The first is expensive and the second does not leave time. So we will use the same sequencer as the best rollup version and post the same important files online in the ZK version of Arbitrum.

If anyone is bragging that ZK can pack a snapshot of recordings in an instant, be careful. If you only post one of the files after a long time, it means you haven't given the end of that time.

Conclusion: Due to pragmatic decisions, the best stacking and ZK systems must be completed in the same way and on time.

Optimistic Rollup and ZK: the strength of unconditional confidence

The power of unshakeable faith means that anyone can force the body to change. (Religious security tools are available to ensure this achievement is correct.)

An optimized rollup ensures that every node declaration is completed. To complete the request, the node must perform a string exchange and then drop a string, which can only be returned after the process confirms the request.

To be successful in the ZK system, each node must be able to generate and publish one of the required ZK credentials with the status string. This requires hardware and software that is easily accessible to everyone. Therefore, there is no need to design or purchase special equipment, and it is not possible to make very large equivalents. There must be a way to generate valid ZK certificates on the correct device. A ZK service provider who does not provide these services or publish figures generating evidence for a system does not provide consistent reliability and does not guarantee the operation of the system. Their system is centralized because only specialized parties can force the process. (It is uncertain whether the best ZK service providers can be recognized by the average user.)

Conclusion: The progression of unconditional trust is easier in an optimistic stacking system.

ZK vs. Bullish cumulative: connection

One area where ZK stacking has advantages is related to Ethereum. The race rollup is expected to delay the transfer of money from race to L1 by one week, while the ZK rollup allows drawdown immediately after the publication of the ZK proof to L1. In practice, it doesn't make much difference as bullish rollup users can take advantage of the fast service that converts their L2 funds to lower L1 funds. Thus, the advantage of ZK in general is that users do not have to pay a small fee which is paid by the connected services (which compete in terms of cost). It's not just theoretical. There are a number of rapidly growing services out there today that include Arbitrum Quick Removal.

It is important to note that the integration benefits of the ZK cumulation are limited. This only applies to L2 for Ethereum extensions. Once upon a time (circa 2019), many people believed that the competition would be slowed down by the live dapp. In this world, roll-up users will definitely find themselves in L1 and L2. But that's not the world we live in. Arbitrum has a thriving ecosystem with hundreds of dApps in every corner of Defi, and many users are building bridges with Arbitrum and staying there for a long time. Also, users don't go to Ethereum because they cross multiple chains. They will also use different L1s and side chains, and the ZK rollup is no better than the most optimistic for a direct connection.

Summary: The ZK system has some advantages for connection to and from L1, but it has been abandoned a lot in practice due to its fast connection and multiple cable connections.

concludes

Comparing the bullish rollup system to the ZK system, I think the rollup competition is real. The best idea is to be cheaper and work better with EVM and existing devices, but the only downside is that the L1 connection will be slower without any support for fast connection. Another advantage of ZK is that it comes from the visible cost or the speed of the chain, which I don't think is what consumers want.

None of this will change. Completing the ZK certified EVM-compliant contract will also be more expensive than achieving the expected quality, and the requirements for completeness, chain visibility and distribution remain the same. If things change, we're always ready to upgrade Arbitrum to ZK-based operation, but we don't think we will.

In the end, fill in carefully. People like to compare the Arbitrum available now to the ZK system representing the future. However, if we compare the technology available today, this comparison does not make sense because prospects like Arbitrum are the only ones who support the public export of smart contract. Or, if you are comparing the systems of the future, you should compare the Arbitrum of the future to the ZK system of the future. We are constantly improving Arbitrum. For example, future versions of Nitro may include improvements in cost savings and data loss in supply chains. We are constantly working to improve Arbitrum and bring its value to theoretical limits. As this report suggests, we believe that the best prospects are indeed given current procedures and the theoretical limitations of each.