What are the similarities and differences between Ethereum 2.0 and other Layer 1 expansion solutions?

• Crypto Valley Live (ID: cryptovalley)

• , Author: Mika Honkasalo, translation: Li Hanbo, reproduced by Odaily with authorization.

• Summary

Layer 1 of most next-generation blockchains scales with a parallel architecture, distributing transaction processing to different nodes

The challenge with sharded ecosystems is that they break composability - unless smart contracts are deployed on the same shard or blockchain, they cannot call each other synchronously

Most of the well-known next-generation blockchain projects plan to scale with a parallelized scaling architecture. In the case of Ethereum 2.0 and NEAR, it is called sharding, while in the case of Polkadot and Cosmos, it is more often referred to as interoperability between blockchains.

From a top-down perspective, each of these solutions looks similar. Transactions are processed with different sets of validators, and there are some similar communication methods between different environments. This is the same for sharding on Ethereum 2.0 and specific application chains on Cosmos.

Some tradeoffs in the design:

Ethereum 2.0

Shared Security vs. Sovereignty: where each node derives security from a global set of validators, or is responsible for its own security.

Heterogeneity vs. homogeneity: where each connected shard is like every other shard, or connected chains can have different properties (such as different consensus mechanisms or supported programming languages).

Sharding in Ethereum 2.0 is based on the simple goal of dividing transaction processing and storage requirements between shards. In the current version of Ethereum, each node is required to verify all transactions and store all historical information of Ethereum."main chain"In practice, this means that from among the Proof-of-Stake nodes on Ethereum 2.0 acting as validators, a subset is assigned to a shard. A leader is chosen at random to take on a role similar to the winning miner in Bitcoin's proof-of-work — producing a block while a committee of other validators attests to the block's validity.

Once the committee has proven the validity of a block, it can be included"slot"main chain"epoch"(Beacon Chain). This proof will be stored in the Beacon Chain instead of storing the entire transaction history of the shard.

The committee creates timeframes for shard blocks, called

. 32 slots form a

, after which the committee is dissolved and the shards are reorganized with new participants. The first slot of each epoch is a checkpoint where previous blocks can be finalized. The epoch loops every 6.4 minutes.

The solution is random sampling and regular rotation of validators.

Polkadot

Each shard committee must have at least 128 members, and if you randomly select validators from around the world, the distribution of those chosen follows a binomial distribution. For example, if you assume that 150 members are selected from a global pool of contributors (ETH 2.0 token holders) with an honesty rate of 75%, then the probability that this shard is also honest is 99.999999998%.

Infrequent random sampling presents a new attack method where validators know which shard they are on at a given time period and can start bribing other committee members on the same shard. Sampling has overhead because every time a validator is elected to a new shard, they need to download the entire shard's data.

secondary title

Ethereum 2.0 uses shared security, where ETH holders verify transactions on the same shard. Polkadot also implements shared security, but uses different shards, allowing each shard to have its own token and governance rules.

Typically, these shards or parallel chains are built on Substrate, a blockchain development framework. If a chain decides to connect to the relay chain, DOT holders become security providers for the parachain. If a chain wants to be part of the Polkadot consensus, they must lease a parachain slot through an auction.

Polkadot uses a variant called Nominated Proof-of-Stake (NPoS). Nominators are DOT holders who vote for validators. Currently, the network is in the process of scaling up the validator size from 20 to 100 during the launch phase.

Each parachain connected to the Relay Chain has collators who run a full node of the parachain and package their transactions into blocks. These blocks are then submitted to validators on the relay chain that have been assigned to a given parachain. Similar to Ethereum 2.0, these validators are randomly rotated to new parachains on a regular basis."How these validators are incentivized is up to the parachain - for example, validators for a given parachain can be incentivized by giving the parachain's native token. Collators provide validators of a parachain with a Merkle tree of the most recent state transition -- a sort summary and unique fingerprint of a given block in the blockchain. Then, the relay chain validators check whether the block follows the state transition rules of the parachain."It should be noted that Polkadot does not guarantee the validity of the state, only checks the state transition. In practice, this means that when a parachain joins Polkadot's consensus, its previous state is considered valid.

candidate receipt

Cosmos

, and is eventually included in the state of the relay chain. On the relay chain, the estimated time for a finalized block is 12-60 seconds. Polkadot is also working on a cross-chain messaging protocol that would allow parachains to communicate without going through the relay chain."lightest "Compared with Ethereum, one of the differences brought about by giving parachains the right to be responsible for their own tokens is that the transaction fees on parachains can be customized. Parachains can choose their own fees within the system, while the security and resources of the relay chain are paid through the auction mechanism.

secondary title

Compared to Polkadot and Ethereum, Cosmos has taken

The cross-chain communication method separates its own security from the security of the entire system. Cosmos Hubs only validate messages between connected blockchains.

The Cosmos SDK is a framework for building application-specific blockchains (or zones) that are interoperable with the rest of the Cosmos ecosystem.

For example, if MakerDAO were hacked today, MKR holders would have to convince ETH owners to fork the blockchain. The bar to do so is much higher than if MakerDAO were its own blockchain.

NEAR Protocol

What is special about Cosmos is the increased flexibility for developers - they have full control over the virtual machine, consensus mechanism or governance method they want. All Cosmos needs is a light client proof.

However, the Cosmos model requires the market to take on a larger role in dealing with the risk of failure. For example, a fast-confirming version of an anchor token might have a different price than a slower version of the same token. Essentially, security can be priced as an asset rather than a blockchain design."secondary title"The sharding design (Nightshade) of the NEAR protocol has the same core attributes as Ethereum 2.0. NEAR holders are responsible for the security of all shards, which are homogeneous. The main difference between the two is that Near cancels the beacon chain.

NEAR does not have a main chain, but a single chain containing blocks, which carries all transactions that have occurred. However, physically, each validator maintains only one shard of the transactions they validate (

piece

) corresponding to the state.

Transactions in a block are allocated in different chunks. The block itself contains only these chunks. Unlike Polkadot and Ethereum 2.0 where the main chain and shard chains have two separate consensus processes running, NEAR has only one consensus process to maintain the chain.

This is achieved by validators being assigned to both block production and some subset of shards. Within these shards, validators take turns producing blocks. Each block producer then waits for the block producer to send them an erasure-coded version of the block — which is then used to create the next block.

NEAR maintains fast cross-shard calls between contracts with receive transactions. When a transaction affects the state of another chunk, a receipt is sent to the blockchain. Each chunk observes the most recent blocks and the receipts assigned to them, and applies these receipts in its own transactions.

The tradeoff for NEAR is that the current design can handle up to ~200 validators, whereas Ethereum can have any user with 32 ETH as a validator (millions of validators). This is because of the constant communication requirement between chunk producers and block producers (aim for a block time between 2-3 seconds).

in conclusion

However, the main advantage of NEAR's sharding design is that it is relatively easy to implement compared to Ethereum 2.0 and Polkadot.

secondary title

in conclusion

The concern with sharding or similar blockchain ecosystems is that they limit composability. It cannot support the interaction of different contracts and the upgrade of transactions. After a trade-off, Cosmos' cross-chain transactions may be the slowest, while shard chains with homogeneous security are the fastest.

With limited composability, sharding designs like Ethereum 2.0 do offer potentially massive scalability. Ethereum 2.0 will be rolled out in three phases, the last of which will enable smart contracts. However, after the second phase, using Ethereum as the data layer, the transaction processing capacity can be increased to 50,000 transactions per second through Optimistic or ZK Rollup.

"Collectively, each of these layer1 constructs scales exponentially better than today. However, it is worth noting that they are also highly similar."Meaningful differences between different blockchains may have more to do with timing — i.e. when projects will be able to launch a version that is competitive with Ethereum. Today, most projects are built on Ethereum because it is available and all assets and other developers are there.

Today, Ethereum users pay $10-$50 in gas fees for common smart contract interactions, and the race is on to provide more transaction processing, whether it is layer1 or layer2 scaling solutions such as Optimistic and ZK Rollup. Existing high gas fees are perhaps the best chance to start another successful ecosystem. So far, only the Bitcoin and Ethereum chains have seen a meaningful boost.

Unlimited smart contract capabilities