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6 votes

Is Polygon (Matic) a layer-2 or a sidechain?

Short Answer: Polygon PoS can be considered as a combination of sidechain and layer2 solution because it is a separate chain that has its own consensus mechanism but also uses the main Ethereum layer ...
Rosen Santev's user avatar
4 votes

how does optimistic rollup work?

There are many details to optimistic rollups. Nika's example can be used to explain some of the main ideas. 10 ETH is locked on L1 Note that the L1 rollup contract does not know that the 10 ETH ...
eth's user avatar
  • 86.1k
4 votes

how does optimistic rollup work?

Since L1 contract doesn't verify anything about submitted blocks apart from some basic stuff, a malicious sequencer can do all kinds of nasty stuff, like for example adding an invalid transaction that ...
Poma's user avatar
  • 171
4 votes
Accepted

Is Polygon (Matic) a layer-2 or a sidechain?

A blockchain doesn't exclusively have to be one or the other - it can be both a sidechain and a layer-2. They aren't opposites. A sidechain refers to a blockchain which has it's own consensus ...
Janac Meena's user avatar
4 votes

What exactly is Ethereum's Layer 2

Layer 2 means any scaling mechanism that isn't programmed into the Ethereum protocol, i.e. it has no specific effect on consensus. This includes state channels (which Raiden would fall under), Plasma, ...
natewelch_'s user avatar
  • 12.2k
3 votes

Is Polygon (Matic) a layer-2 or a sidechain?

A significant difference between layer 2 and sidechain - Sidechains have security mechanisms of their own. Layer 2 solutions derive their security from their parent blockchain while using their own ...
adiaholic's user avatar
3 votes
Accepted

Does smart contracts "sync" between Polygon and Ethereum?

1 - Do I have to redeploy the contract on the Polygon network or does it automatically sync with the Ethereum Mainnet after it is deployed? Polygon and Ethereum are separate blockchains and do not ...
Mikko Ohtamaa's user avatar
3 votes
Accepted

How to broadcast a transaction directly to a centralised sequencer (Arbitrum/Optimism/others)

You can send transactions directly to the sequencer by using their RPC url. These RPC only support eth_sendRawTransaction (or eth_sendRawTransactionConditional), so for example you can't use them to ...
0xSanson's user avatar
  • 3,339
2 votes

Any Solidity-based sparse merkle tree implemenations in production?

The ETH 2 deposit contract implements a sparse Merkle tree that holds $14B of Ether at the time of writing this answer.
user10030's user avatar
2 votes
Accepted

How to deploy smart contracts to any arbitrary available address like it was done through a regular transaction on Optimism?

I found the reason how Optimism was able to reserve both the 0x4200000000000000000000000000000000000014 and 0x4200000000000000000000000000000000000042 contract addresses, even though they deployed to ...
Ahmed Ihsan Tawfeeq's user avatar
2 votes

Differences between on zkEVM and zkSync ERA

ZkSync Era uses its LLVM compiler, which compiles code from various popular EVM languages such as Solidity, Vyper and Yul to run on their custom zkSync VM. This compiler will be further developed to ...
Inzamam Shakir's user avatar
2 votes
Accepted

Does arbitrum / optimism / other L2s have MEV?

Due to the fact that the sequencer is the "real" node that sequences transactions, I would imagine that is the true MEVer... Correct. But for example, could I run an Arbitrum node and MEV ...
Ake's user avatar
  • 1,148
2 votes

In optimistic roll-ups, can a validator post a valid block that builds on an old-but-invalid block which was not challenged?

The best answer is probably "undefined". Before speculating on an answer, it is important to state the 2 main assumptions of an optimistic rollup: a trust model of 1-of-N: there are many ...
eth's user avatar
  • 86.1k
1 vote

Polygon (MATIC) is a Coin or Token?

If we are talking Polygon - it is a native asset, which is used to pay fees, and is treated like Ether on Ethereum, meaning it is a coin. But as far as it was initially launched as an ERC20 token on ...
Juurou's user avatar
  • 36
1 vote

How does one create and send TXs on L2 - Arbitrum and others?

The algorithm should be the same because every L2 Ethereum chain works with the EVM (Ethereum VIrtual Machine). It is the algorithm every L2 ethereum chain uses
ShadowOfSights's user avatar
1 vote
Accepted

Queries on Base Chain layer 2

if you want to use Base protocol addresses, L1 contract addresses, and L2 contract addresses, you will need to use Base Chain JS SDK or another compatible Ethereum development kit. Here is the general ...
Naveed Ali's user avatar
1 vote
Accepted

are there any other off-chain scaling solution then layer-2?

I would say the actual definition of a "layer 2" varies a bit. Some sources say it should be a real blockchain which utilizes layer 1 for security. I think it's generally agreed that it ...
Lauri Peltonen's user avatar
1 vote
Accepted

How can privacy roll-ups like Aztec make my transfer cheaper?

Transactions from L1 to Aztec are not cheaper - you have to pay the regular L1 transaction fees. Aztec uses zk-rollup technology. On top of that, they use real ZK (which they tend to call zk-zk-rollup)...
Lauri Peltonen's user avatar
1 vote
Accepted

Will Layer-2s and zk roll-ups become redundant once Eth 2.0 sharding and scaling arrives?

Now this is just my speculation, but I don't think L2s will disappear. There is no way to get all three components right of the blockchain trilemma: security, decentralization and scalability. ...
Lauri Peltonen's user avatar
1 vote

Will Layer-2s and zk roll-ups become redundant once Eth 2.0 sharding and scaling arrives?

Here is my theory: If Ethereum gas fees become as cheap as ie., today's Polygon: New Dapp devs will turn a blind eye on L2 and just build new systems in Ethereum, the reason is simple; Market ...
Casareafer's user avatar
1 vote
Accepted

is layer0 and layer-1 blockchain both mainnet?

Layer 0 methods, or network layer methods, are where the mechanism to improve interoperability and scalability operate at the network level of the blockchain architecture stack. Layer 1 methods are ...
Yongjian P.'s user avatar
  • 4,218
1 vote
Accepted

web3js returns empty array on getPastEvents on polygon, optimism and arbitrum

@Ismael points out to change the provider and when I have changed the provider, the code works correctly.
Mostafa's user avatar
  • 51
1 vote

Where are layer 2 transactions (e.g. on Loopring Exchange) actually processed?

I'm not very familiar with Loopring specially, so let me give you a generic answer instead. It's basically up to the L2 to decide and it can be anything. Most L2s start with centralized server(s) ...
Lauri Peltonen's user avatar
1 vote
Accepted

Transferring weth from my contract to an other wallet address on polygon without using bridges

It's not quite possible in solidity, but you can always use 3rd party centralized way of doing it You can read event on the frontend whenever funds are transferred and then you can basically send ...
Talha Sajid Chaudhary's user avatar
1 vote

Transferring weth from my contract to an other wallet address on polygon without using bridges

Each blockchain (Ethereum and Polygon for example) have their own storages, and cannot be accessed one with other. Its only possible to manage with 3rd party backends that could monitor both ...
gazoblock's user avatar
  • 346
1 vote

Is Polygon (Matic) a layer-2 or a sidechain?

Sidechain is another blockchain that is connected to Ethereum by a two-way peg which allows users to transfer funds from the main chain to the sidechain and from the sidechain to the main chain. So ...
Yilmaz's user avatar
  • 1,705
1 vote

Questions regarding Polygon Network Mapping

You need to deploy first on Ethereum, and then submit Token Mapping request or deploy it yourself ChildMintableERC721, this ChildMintableERC721 must be on Polygon's network based on their ...
Adam Boudj's user avatar
  • 2,411
1 vote
Accepted

Can you use Ethereum wallet to receive/send tokens of layer 2 blockchains?

Ethereum private keys and accounts (addresses) are the same across different Ethereum Virtual Machine (EVM) based blockchains. You can make a wallet work in another network by simply switching the ...
Mikko Ohtamaa's user avatar
1 vote
Accepted

How is circuit integrity of ZK-rollups checked by the L1 contract?

After reading the PLONK paper again, I noticed that $q_m$, $q_l$, $q_r$ etc are preprocessed and fixed as input to the verifier, which specify the circuit. That is to say, the circuit is not provided ...
Yuq Wang's user avatar
1 vote

layer 2 solution best option

For now, I would say the best options still seems to be Polygon. Although it's still a sidechain to be exact, and not yet a layer 2 solution. My reasons for choosing Polygon are: It is still where ...
Ahmed Ihsan Tawfeeq's user avatar

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