Comparison of the Development Directions of Ethereum and Solana

Ethereum is undergoing supply-side reform. After the dream of an infinite garden was shattered, Vitalik began to constrain the development of L2/Rollup and more actively defend the L1 track. The "speeding up and cost reduction" plan for the Ethereum mainnet has been put on the agenda, and the shift to Risc-V is just the beginning. How to catch up with or even surpass Solana in terms of efficiency will become the focus in the coming period.

At the same time, Solana continues to expand its consumption demand scenarios. Solana's strategy is "scale up or die," firmly committed to the path of becoming a stronger L1. In addition to the Firedancer developed by a trading platform entering the deployment process, the Alpenglow consensus protocol from the Anza team attracted widespread attention at the recent Solana conference in New York.

Interestingly, Ethereum's ultimate goal is to become the world computer, and Alpenglow has a similar vision.

20% Security Consensus in the Era of Large-scale Nodes

Since the birth of Bitcoin, the number of nodes and the degree of decentralization have always been regarded as important indicators for measuring the level of decentralization of blockchain networks. To avoid centralization, the security threshold is typically set at 33%, meaning that no single entity should exceed this proportion.

Driven by capital efficiency, Bitcoin mining ultimately formed mining pool clusters, while Ethereum became the main stage for certain institutions and exchanges. However, this does not mean that these entities can control the operation of the network. Under the model of "maintaining the network - obtaining incentives/management fees," they have no motive to do harm.

However, assessing the health of a network must take its scale into account. For example, in a small group of only three people, a 2/3 majority is needed to be considered effectively operational. Merely pursuing an arbitrary minimum security guarantee of 1/3 is meaningless, as the remaining two can easily collude, making the cost of wrongdoing very low while the potential gains could be high.

In contrast, if it is a large-scale network with 10,000 nodes, there is no need to pursue a 2/3 majority. Outside of the incentive model, most nodes do not know each other, and the coordination cost of collusion among major entities is also too high.

So, if we appropriately reduce the number of nodes and the consensus ratio, can we achieve "speed up and cost reduction"?

This is exactly the idea behind Alpenglow. It plans to maintain a scale of about 1,500 nodes while reducing the security consensus to 20%. This not only improves the node confirmation speed and allows nodes to earn more mainnet incentives, but also encourages the scale of nodes to expand to around 10,000.

It remains to be seen whether this approach will produce an effect of 1+1>2 or break through existing security mechanisms. However, this line of thought is very much in line with Solana's style, participating in public chain competition as a competitor to Ethereum.

Alpenglow's Technological Innovations

The theoretical basis of Alpenglow is that, in the era of large-scale nodes, a high consensus number is not required. Because under the PoS mechanism, wrongdoers need to mobilize enormous capital to control the network. Even with only a 20% consensus ratio, it would require $20 billion to control Ethereum and $10 billion to control Solana at current prices.

With such a large amount of funds, choosing other investment methods may be more attractive. Moreover, even if someone attempts to control the blockchain, they will face retaliation from the remaining 80% of nodes, unless it is a state-level action.

In terms of specific implementation, Alpenglow roughly divides the entire process into three parts: Rotor, Votor, and Repair. This is, to some extent, a deep transformation of the existing Turbine mechanism on Solana.

Turbine is Solana's block broadcasting mechanism, responsible for disseminating block information to achieve consensus confirmation among all nodes. Unlike the Gossip protocol used in the early design of Ethereum, Turbine adopts a hierarchical propagation approach:

1. In each cycle, nodes are divided into Leader, Relay, and ordinary nodes, only Leader nodes can send block broadcast information.

2. A small number of Relay nodes receive information and continue to broadcast it to more regular nodes, forming a propagation network similar to a tree structure.

In Alpenglow, this variant of the mechanism is called Rotor, which is essentially an ordered block message propagation method, where no Leader or Relay node is fixed.

Votor is a node confirmation mechanism. In the vision of Alpenglow, if the first round of node voting reaches 80%, meeting the minimum requirement of over 20%, it can be directly approved quickly. If the first round of voting is between 60% and 80%, a second round of voting can be initiated, and if it exceeds 60% again, it can be confirmed finally.

If consensus cannot be reached, the Repair mechanism will be activated. However, this situation may indicate that the protocol is facing serious issues, similar to the scenario during a bank run.

The core idea of Alpenglow is to reduce the block consensus generation process, rather than simply increasing hardware resources to improve bandwidth. If the data blocks can be controlled to around 1500 bytes and the generation time can be significantly shortened (with tests achieving speeds as fast as 100 milliseconds), it will greatly enhance network performance.

Conclusion

After MegaETH, existing L2 solutions have basically reached their limits. With SVM L2 unable to gain support from Solana, the Solana mainnet has a real need for continued expansion. Only by increasing the mainnet TPS to overwhelm all competitors can Solana truly realize its vision of being an "Ethereum killer."

It is worth noting that the application range of Alpenglow is not limited to Solana. In theory, any PoS chain, including Ethereum, can adopt this mechanism. This reflects that current blockchain research is close to the technological boundary and urgently needs more innovative ideas from the fields of computer science and even sociology.

Once, someone predicted that the world only needed a few large computers. If we consider the HTTP-TCP/IP-based internet as one of them, along with Bitcoin and Ethereum, then there is indeed not much room left for the development of Solana. But it is precisely this competitive pressure that drives blockchain technology to keep advancing.