In-depth Analysis of the Technical Differences Among Ethereum, Solana, and Aptos in the Transaction Lifecycle

Comparing the technical characteristics of different public chains may seem complex due to varying perspectives. To accurately understand the differences between Aptos and other public chains, we can choose the lifecycle of a transaction as a starting point. By analyzing the complete process of a transaction from creation to final state update, including creation and initiation, broadcasting, ordering, execution, and state update, we can clearly grasp the design philosophy and technical trade-offs of each public chain.

All blockchain transactions revolve around these five steps. This article will focus on Aptos, analyze its unique design, and compare it with Ethereum and Solana.

Aptos: Optimistic Parallelism and High-Performance Design

Aptos is a high-performance public chain that has a transaction lifecycle similar to Ethereum, but achieves significant performance improvements through unique optimistic parallel execution and memory pool optimization.

Create and Initiate

The Aptos network consists of light nodes, full nodes, and validators. Users initiate transactions through light nodes (such as wallets or applications), which forward the transactions to nearby full nodes, and the full nodes then synchronize with the validators.

broadcast

Aptos retains the memory pool, but the memory pools do not share after QuorumStore. Unlike Ethereum, its memory pool is not just a transaction buffer. After transactions enter the memory pool, the system performs pre-sorting based on rules (such as FIFO or Gas fees) to ensure that there are no conflicts during subsequent parallel execution. This design avoids the high hardware requirements that come with needing to declare read and write sets in advance.

sorting

Aptos adopts the AptosBFT consensus, where proposers generally cannot freely order transactions. The memory pool pre-sorting has been completed in advance to avoid conflicts, and block generation relies more on collaboration among validators rather than being led by proposers.

execute

Aptos uses Block-STM technology to achieve optimistic parallel execution. Transactions are assumed to be conflict-free and processed simultaneously; if a conflict is detected after execution, the affected transactions will be re-executed. This method leverages multi-core processors to enhance efficiency, with TPS reaching up to 160,000.

Status Update

Validator synchronization status, finality confirmed by checkpoints, similar to Ethereum's Epoch mechanism, but more efficient.

Aptos's core advantage lies in the combination of optimistic parallelism and pre-sorting of the memory pool, which reduces node performance requirements while significantly increasing throughput.

Ethereum: Benchmark for Serial Execution

Ethereum, as the pioneer of smart contracts, is the origin of public chain technology, and its transaction lifecycle provides a foundational framework for understanding Aptos.

Ethereum transaction lifecycle

• Creation and Initiation: Users initiate transactions through their wallet via relay gateways or RPC interfaces.
• Broadcast: The transaction enters the public memory pool, waiting to be packed.
• Sorting: After the PoS upgrade, block builders package transactions based on the principle of profit maximization, and submit them to the proposer after bidding on the relay layer.
• Execution: EVM processes transactions serially and updates state in a single thread.
• Status Update: Blocks must be confirmed for finality through two checkpoints.

The serial execution and memory pool design of Ethereum limit its performance, with a block time of 12 seconds per slot and low TPS. In contrast, Aptos has achieved a qualitative leap through parallel execution and memory pool optimization.

Solana: Ultimate Optimization of Deterministic Parallelism

Solana is known for its high performance, and its transaction lifecycle is significantly different from Aptos, especially in terms of memory pool and execution methods.

Solana transaction lifecycle

• Create and Initiate: Users initiate transactions through their wallets.
• Broadcasting: No public memory pool, transactions are sent directly to the current and the next two proposers.
• Sorting: Proposers package blocks based on PoH (Proof of History), with block time of only 400 milliseconds.
• Execution: The Sealevel virtual machine adopts deterministic parallel execution, requiring the declaration of read-write sets in advance to avoid conflicts.
• Status update: BFT consensus quick confirmation.

The reason Solana does not use a memory pool is that it could become a performance bottleneck. Without a memory pool, and due to Solana's unique PoH consensus, nodes can quickly reach consensus on the order of transactions, eliminating the need for transactions to queue in a memory pool, allowing them to be executed almost instantly. However, this also means that during network overload, transactions may be discarded rather than waiting, and users will need to resubmit.

In contrast, Aptos's optimistic parallelism does not require declaring read-write sets, the node threshold is lower, yet the TPS is higher.

Two Paths of Parallel Execution: Aptos vs Solana

The execution of a transaction represents the update of the blockchain state; it is the process of converting the transaction initiation instructions into a state with finality. Parallel execution refers to the process of multi-core processors calculating the network state simultaneously. Currently, parallel execution in the market is mainly divided into two methods: deterministic parallel execution and optimistic parallel execution.

• Deterministic Parallelism (Solana): The read and write set must be declared before broadcasting the transaction. The Sealevel engine processes non-conflicting transactions in parallel based on the declaration, while conflicting transactions are executed serially. The advantage is efficiency, while the disadvantage is high hardware requirements.

• Optimistic Concurrency (Aptos): Assuming transactions have no conflicts, Block-STM verifies after parallel execution, and if there are conflicts, it retries. Pre-sorting the memory pool reduces conflict risk and lightens the load on nodes.

For example: Account A has a balance of 100, transaction 1 transfers 70 to B, transaction 2 transfers 50 to C. Solana preemptively confirms conflicts through declarations and processes in order; Aptos, after parallel execution, adjusts if it finds insufficient balance. The flexibility of Aptos makes it more scalable.

Optimistic parallelism for early conflict confirmation through memory pool

The core idea of optimistic concurrency is to assume that transactions processed in parallel will not conflict, therefore the application side does not need to submit a transaction declaration before the transaction execution. If a conflict is found during verification after the transaction execution, Block-STM will re-execute the affected transactions to ensure consistency.

On Aptos, after transactions enter the public memory pool, they are pre-sorted according to certain rules (such as FIFO and Gas fees) to ensure that transactions within a block do not conflict when executed in parallel. This pre-sorting of transactions is key to Aptos's implementation of optimistic parallelism. Unlike Solana, which requires transaction declarations, Aptos does not need this mechanism, thus significantly lowering the performance requirements for nodes. In terms of network overhead to ensure transaction non-conflict, the impact of the memory pool on TPS in Aptos is much less than the cost of introducing transaction declarations in Solana. As a result, Aptos's TPS can reach 160,000, more than double that of Solana.

The narrative based on security is the development direction of Aptos.

RWA (Real World Assets)

The advantages of Aptos in the RWA field:

• Block-STM can process multiple asset transfer transactions in parallel, avoiding confirmation delays caused by network congestion.
• The memory pool pre-sorting ensures that transactions are executed in order, maintaining the reliability of asset records.
• The modular design and security of the Move language facilitate the construction of complex RWA applications.

Aptos's progress in the RWA field:

• In July 2024, USDY, introduced by Ondo Finance, has a market value of approximately $15 million on Aptos as of March 10.
• In October 2024, Franklin Templeton will launch the BENJI token on Aptos.
• Collaborating with Libre to promote security tokenization, involving investment funds from Brevan Howard, BlackRock, and Hamilton Lane.

stablecoin payment

Aptos's advantages in the stablecoin payment sector:

• The resource model of the Move language prevents double spending and ensures the accuracy of stablecoin transfers.
• Low gas fees make it highly competitive in small payment scenarios.
• The memory pool pre-sorting and Block-STM ensure the stability and low latency of payment transactions.
• AptosBFT's decentralized consensus reduces centralized risks while supporting developers to embed KYC/AML checks.

Future Development Directions:

• Promote the widespread adoption of stablecoins
• Build a cross-border payment network
• Collaborate with payment giants to develop an on-chain settlement system
• Supports micro-payment scenarios, such as real-time rewards for content creators.

Summary: The Technical Differences and Future Narrative of Aptos

Aptos integrates security and efficiency considerations into key aspects of the transaction lifecycle, achieving a balance between performance and safety in its design. The pre-sorting of the memory pool combined with Block-STM's optimistic concurrency reduces the threshold for nodes while achieving high throughput. This "seeking speed while maintaining stability" approach, complemented by the resource model of the Move language, grants Aptos higher security.

Aptos demonstrates great potential in the fields of RWA and PayFi. In terms of RWA, its high throughput supports large-scale asset on-chain; in PayFi and stablecoin payments, low cost, high efficiency, and compliance support micropayments and cross-border settlements.

In the future, Aptos is expected to connect traditional finance with the blockchain ecosystem through the narrative of "security-driven value network," continuously making strides in the fields of RWA and PayFi, and building a new public chain pattern that combines trust and scalability.