Transaction Lifecycle Perspective: Analyzing the Technical Differences between Ethereum, Solana, and Aptos

Comparing the technical characteristics of different public chains may seem tedious and boring. To quickly and accurately grasp the differences between Aptos and other public chains, this article chooses the transaction lifecycle as the entry point, analyzing the complete process of a transaction from creation to final state update, including five steps: creation and initiation, broadcasting, sorting, execution, and state update.

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

Aptos: Optimistic Concurrency and High-Performance Design

Aptos is a high-performance public blockchain that has a transaction lifecycle similar to Ethereum, but achieves significant 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, which forward the transactions to nearby full nodes, and the full nodes then synchronize with the validators.

broadcast

Aptos retains the memory pool, but it is not shared between memory pools after QuorumStore. Unlike Ethereum, its memory pool is not just a transaction buffer. After a transaction enters the memory pool, the system performs pre-sorting based on rules to ensure that there are no conflicts when transactions are executed in parallel subsequently. This design avoids the high hardware requirements of Solana, which needs to declare read and write sets in advance.

sorting

Aptos adopts the AptosBFT consensus, where proposers are generally unable to freely order transactions. AIP-68 grants proposers the additional right to fill in delayed transactions. The pre-sorting of the memory pool has been completed in advance to avoid conflicts, and block generation relies more on collaboration among validators.

Execute

Aptos utilizes 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 approach 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.

The core advantage of Aptos lies in the combination of optimistic parallelism and pre-sorting of the memory pool, which reduces the performance requirements of nodes while greatly enhancing 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 the 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 profit maximization principles and submit them to the proposer after bidding on the relay layer.
• Execution: EVM processes transactions serially, updating state in a single thread.
• Status update: Blocks must pass through two checkpoints to confirm finality.

The serial execution and memory pool design of Ethereum limit performance, with a block time of 12 seconds per slot and a low TPS. In contrast, Aptos achieves 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 differs significantly 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 a block time of only 400 milliseconds.
• Execution: The Sealevel virtual machine adopts deterministic parallel execution and requires the declaration of read and write sets in advance to avoid conflicts.
• Status update: BFT consensus rapid confirmation.

The reason Solana does not use a memory pool is that it could become a performance bottleneck. Without a memory pool, and with 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 processed almost instantly. However, this also means that during network overload, transactions may be dropped rather than waiting, requiring users to resubmit.

In contrast, Aptos's optimistic parallelism does not require the declaration of read-write sets, has a lower node threshold, and yet achieves a higher TPS.

Two Paths of Parallel Execution: Aptos vs Solana

The execution of a transaction represents an update of the block state, which is the process of converting the transaction initiation instruction into a finalized state. Parallel execution in blockchain refers to the process of multi-core processors calculating the network state simultaneously. Currently, parallel execution in the market is divided into two types: deterministic parallel execution and optimistic parallel execution.

Aptos and Solana have chosen different directions:

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

• Optimistic Parallelism (Aptos): Assuming no conflicts in transactions, Block-STM executes in parallel and then verifies. If there is a conflict, it retries. Pre-sorting in the memory pool reduces the risk of conflicts and lightens the load on nodes.

Optimistic parallelism completes conflict confirmation in advance through the 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 execution. If a conflict is found during validation 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 to ensure that transactions within a block do not conflict during parallel execution. This pre-sorting of transactions is key to Aptos's implementation of optimistic parallelism. Unlike Solana, which requires the introduction of transaction declarations, Aptos does not need this mechanism, significantly reducing the performance requirements on nodes. In terms of network overhead to ensure transaction non-conflict, the impact of the memory pool on TPS in Aptos is much smaller than the cost of introducing transaction declarations in Solana. Therefore, 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

Aptos is actively promoting the tokenization of real-world assets and institutional financial solutions. Compared to Ethereum, Aptos's Block-STM can process multiple asset transfer transactions in parallel, avoiding confirmation delays caused by network congestion. Aptos's memory pool pre-sorting ensures that transactions are executed in order, maintaining the reliability of asset records even during peak periods.

The modular design and security of the Move language allow developers to more easily build reliable RWA applications. Aptos's potential in the RWA field lies in the combination of security and performance. In the future, it can focus on collaborating with traditional financial institutions to bring high-value assets like bonds and stocks on-chain, using the Move language to create highly compliant tokenization standards.

In July 2024, Aptos announced the integration of Ondo Finance's USDY into its ecosystem, and it has been integrated into major DEXs and lending applications. As of March 10, USDY's market capitalization on Aptos is approximately $15 million, accounting for about 2.5% of USDY's total market capitalization. In October 2024, Aptos announced that Franklin Templeton had launched a Franklin on-chain U.S. government money market fund (FOBXX) represented by the BENJI token on the Aptos Network. Additionally, Aptos is collaborating with Libre to promote the tokenization of securities, bringing the investment funds of Brevan Howard, BlackRock, and Hamilton Lane on-chain to enhance access for institutional investors.

stablecoin payment

Stablecoin payments need to ensure the finality of transactions and asset security. Aptos's Move language prevents double spending through a resource model, ensuring the accuracy of each stablecoin transfer. Aptos's low Gas fees make it highly competitive in small payment scenarios. Aptos's memory pool pre-sorting and Block-STM guarantee the stability and low latency of payment transactions.

PayFi and stablecoin payments need to balance decentralization with regulatory compliance. AptosBFT's decentralized consensus reduces centralization risks, while its modular architecture supports developers in embedding KYC/AML checks. Aptos's balanced design makes it more suitable for financial institutions to enter.

The potential of Aptos in the PayFi and stablecoin payment sectors lies in the "security, efficiency, and compliance" triad. In the future, it will continue to promote the large-scale adoption of stablecoins, build cross-border payment networks, or collaborate with payment giants to develop on-chain settlement systems. High TPS and low costs will also support micro-payment scenarios, such as real-time rewards for content creators.

Summary: The Technical Differences of Aptos and Future Narratives

Aptos's design strikes a clever balance between performance and security. Its memory pool pre-sorting combined with Block-STM's optimistic parallelism reduces node thresholds while achieving a high throughput of 160,000 TPS, surpassing Solana's deterministic parallelism and Sui's object-level parallelism. Compared to Ethereum's serial execution, Aptos's parallel capabilities represent a qualitative leap; whereas Solana and Sui's radical optimizations that eliminate the memory pool, Aptos retains the pre-sorting mechanism to ensure network stability under high load.

It is precisely based on this combination of security and performance that Aptos demonstrates tremendous potential in the RWA and PayFi narratives. In the RWA field, Aptos's high throughput supports large-scale asset on-chain, and recent collaborations with Ondo Finance, Franklin Templeton, and Libre have already shown results. In PayFi and stablecoin payments, Aptos's low cost, high efficiency, and compliance support micropayments and cross-border settlement, making it a strong candidate for the "next-generation payment infrastructure."

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