The Incentivized Aleo Testnet 3 Recap
The incentivized Phase 2 of Aleo Testnet 3 lasted from 00:00 UTC on December 2, 2022, to 23:59 UTC on January 31, 2023, a 5-day extension of the initial deadline. A total of 4,4000 nodes joined the network, with over 5 billion proofs submitted per second at its peak, and over 3.1 million Aleo credits distributed to provers. ZKRush also performed admirably on this Testnet, exceeding our expectations and earning favorable feedback from miners. The following is our recap of this incentivized Testnet 3.
The Roll Out of Mining Pool
We established a step-by-step strategy at the outset, regarding business-level client service as the pillar. Once the business operating system is refined and the software performance is steady we would then progressively release the service to the broader market. As a result, during the first several weeks after the incentivized testnet launched, we mainly served business-level clients. It was not until December 29, 2022, that we rolled out the ZKRush mining pool, which was well received by the market, and the pool hashrate swiftly surged, reaching over 16 million proofs submitted per second. This is owing to our open and transparent pricing systems, as well as our cutting-edge and efficient mining algorithms. The launch of the mining pool enabled us to evaluate the compatibility of our mining software on a variety of hardware settings, therefore offering us progressive feedback, meanwhile, broadening the brand’s influence. Simultaneously, the computing power contributed by the mining pool could partially supplement our total power percentage in the network.
First GPU-ONLY Algorithm
ZKRush has steadfastly embraced the GPU-only solution from the start. The GPU implementation is not terribly challenging for us, but the benefits it has achieved in terms of computing power and total cost performance are incomparable to those of CPU-only or combination modes. With the advancement of the testnet, we have also seen the market begin to shift to the GPU solution, which has gradually become the optimal choice, confirming our initial choice. We have an industry-leading GPU acceleration engineering team that is continually optimizing and enhancing our implementation while also significantly increasing in size. We expect that our complete advantages will be further evident in the upcoming incentivized stages.
Introducing New Service Mode
We gained certain technical and service experience in the later stages of the testnet. As a result, we decided to provide software-as-a-service (SaaS) based on our existing services, full-custodial and public mining pool. We provide subscription services to fulfill the customization demands of different user groups in the market while establishing the groundwork for us to open up the sinking market for clients with large computing power who wish to use ZKRush mining software to participate in Aleo testnet.
Aleo Network Structure
The core network structure of this time consists of the centralized Beacon node and 10 official Validator nodes. The prover nodes in the network cannot directly connect to the Beacon node, and can only connect to the Validator node, which implies that if the connection between the Validators and the Beacon fails, the prover nodes have no effective recovery mechanisms. The Phase 2 of Testnet 3 was mostly concerned with the PoSW algorithm, difficulty modification, and smart contract testing. There are no actual transactions included in the proofs submitted.
Overview of PoS + PoSW Design
In Aleo’s consensus mechanism design, Proof of Stake (PoS) and Proof of Succint Work (PoSW) are included. PoSW is actually attached to PoS, similar to Ethereum’s PoS mechanism, and blocks are generated at a constant time interval. Blocks may not necessarily contain PoSW rewards. Only when the coinbase puzzles are solved during the PoSW process, the block will then include the related information of the coinbase solutions, so that the generated blocks will contain rewards. PoS can be considered the carrier of the PoSW chain.
Testnet Failure Review
1) Solution Submission Failure
The Aleo team maintains 10 Validators nodes that are directly connected to the Beacon node. To receive the coinbase puzzles, Provers must connect to these 10 Validator nodes, then execute the PoSW algorithm to generate solutions before sending them to the Validators. After the Validators have verified all of the submissions, they will be forwarded to the Beacon, where they will be included in the blocks generated.
Following the launch of the incentivized testnet, a large number of provers were able to generate solutions and broadcast normally, but their submissions were not included in the blocks generated, resulting in no compensation. We investigated the problem immediately and discovered the root cause: the Beacon node would kick out prover nodes that repeatedly sent the same solutions; in other words, the Beacon node and some Validator nodes could not maintain a stable connection, eventually leading to the problem.
2) Connection Failure between Prover and Validator Nodes
Another major issue during the testnet was the failure of prover nodes to connect to Validators. The source of this problem is that owing to a coding error, the Validator nodes incorrectly assume that a severed connection still exists and refuse to enable a node to establish a new connection, preventing the Prover node from connecting to the Validators.
Outlook for the Upcoming Phase 3
The previous Phase 2 demonstrated that PoSW is feasible, and the following Phase 3 will concentrate on PoS and the staking process. However, the specifics of Aleo’s PoS design have yet to be revealed. According to earlier code analysis, the reward distribution of PoS and PoSW in a block reward is around 1:9, and PoSW continues to have a higher share in future testing. Although the reward for PoS is just one-tenth, it does not need a large amount of resource input. The number of Validators, on the other hand, is restricted and needs a significant sum of Aleo Credits to be staked. Aleo is anticipated to choose 100 Validator nodes in the next phase, however, the criteria have not been announced. In the first half of 2023, Aleo’s final testnet before mainnet will be in full swing, and we will continue to pay attention and provide timely analysis to everyone.