III. Consensus Mechanism
Question 21: What kind of consensus mechanism does SCDO adopt?
Answer: SCDO uses an improved version of the proof-of-work consensus mechanism called ZPoW (Zero Proof-of-Work) consensus. In fact, ZPoW falls within the category of PoW but is optimized to address various issues present in traditional PoW (such as computing power monopolization, resource waste, etc.).
All nodes in the SCDO network participate in block generation competition through hash calculations, with successful participants obtaining the rights to record new blocks and block rewards. Although it is still fundamentally 'computing power reigns supreme', SCDO has innovated on the details of the PoW algorithm to ensure a more fair, efficient, and environmentally friendly competition among miners. It should be particularly noted that the SCDO mainnet does not adopt proof of stake (PoS) or delegated proof of stake (DPoS) consensus mechanisms, but rather adheres to the PoW route, significantly enhancing the fairness and security of PoW through ZPoW.
Question 22: What are the characteristics of the ZPoW consensus algorithm?
Answer: ZPoW is an innovative PoW algorithm with the main characteristics including: First, a focus on scientific computing: the ZPoW algorithm utilizes problems that require continuous computation and are difficult to parallelize (such as matrix computations).
This means that GPUs cannot easily parallel accelerate like processing simple hashes, thus reducing the advantage of professional mining machines over ordinary computers.
Secondly, a multi-target computing framework is adopted: ZPoW designs a hybrid multi-algorithm mining framework where miners can choose different computational tasks, each with independent difficulty and dynamic adjustments. If too many miners for a certain algorithm lead to a high block generation frequency, the network will increase its difficulty and decrease its output probability, thus encouraging miners to switch to other algorithms, making the block generation opportunities more balanced across computational targets. Thirdly, CPU friendly: Through the above mechanisms, ZPoW significantly reduces the advantage of GPU/ASIC over CPU, allowing ordinary hardware to be competitive. Finally, the difficulty of a 51% attack is higher: since attackers must dominate multiple computational targets to continuously produce blocks, the actual initiation of a 51% attack is several times more difficult compared to traditional PoW. Overall, ZPoW inherits the security and censorship resistance of PoW while improving fairness and security margin through technical means, serving as the cornerstone of SCDO network stability.
Question 23: How does ZPoW differ from traditional PoW such as Bitcoin?
Answer: Compared to Bitcoin's SHA-256 PoW, ZPoW differs in both algorithmic form and strategy:
Algorithm Complexity: Bitcoin's PoW seeks simple hash collisions, which can easily be accelerated by ASIC chips; ZPoW, on the other hand, employs complex calculations (such as random matrix determinant calculations), making it difficult to develop dedicated mining machines.
Hardware Friendliness: Traditional PoW heavily relies on high-performance hardware, making it nearly impossible for average users to gain competitiveness with CPUs; ZPoW aims to minimize parallelization advantages, allowing ordinary hardware to participate in mining.
Multi-Algorithm Mixture: Bitcoin has only a single algorithm, resulting in high risks of power concentration; ZPoW introduces various computational tasks to dynamically balance and avoid the monopoly of any single algorithm.
Energy Consumption: Bitcoin's PoW consumes an astonishing amount of electricity due to large-scale computing power competition; ZPoW is designed to be more efficient in computation (useful calculations or reducing unnecessary calculations), resulting in lower energy consumption at the same security level.
Difficulty Adjustment: Both have difficulty adjustment mechanisms to ensure target block generation times; Bitcoin adjusts every 2016 blocks, while SCDO's difficulty adjustment is more flexible (potentially more frequent or algorithmically independent) to adapt to the mixed algorithm architecture. Overall, ZPoW is a deep improvement over traditional PoW, aiming to retain the decentralization and security of proof of work while addressing its efficiency and fairness issues.
Question 24: Why did SCDO choose PoW instead of PoS or other consensus mechanisms?
Answer: Although PoS has gained popularity in many new chains in recent years, SCDO chooses PoW mainly based on the following considerations: First, PoW has been validated over more than a decade by Bitcoin and others, and is considered the most secure and reliable public chain consensus to date, effectively resisting witch attacks and forging historical records. The SCDO team respects Satoshi Nakamoto's fair concept and hopes to continue the security model of 'proof of work = actual resource expenditure'.
Secondly, the entry threshold for PoW is relatively open and transparent—anyone can become a miner to participate in competition, while PoS often has issues with initial allocation inequality or whales monopolizing chips.
SCDO has no pre-mining or private placements, choosing PoW to ensure the fairness of token distribution, so that the network will not be controlled by specific interest groups in its early stages.
Furthermore, from the perspective of decentralization, nodes under the PoW mechanism do not need to trust identities and rely on computing power for consensus, making it easier to achieve global consensus, whereas PoS may weaken decentralization due to the concentration of stakeholders.
Finally, SCDO has optimized the resource consumption and efficiency of PoW through ZPoW, significantly reducing its drawbacks, thus giving more reason to adhere to the PoW route. Overall, SCDO believes that the improved PoW can provide a more solid guarantee of security and decentralization, making it the best choice for achieving the project's vision while compensating for PoW's performance shortcomings through technological innovation.
Question 25: How does ZPoW improve the fairness of ordinary users participating in mining?
Answer: The ZPoW algorithm ensures that more ordinary users can participate in mining and maintain the network through various mechanisms: 1. Reducing hardware gaps: Since ZPoW's problem design requires continuous computation and is not easy to parallelize, professional mining machines and large GPU clusters cannot completely suppress ordinary PCs, allowing home computers, laptops, and even CPUs to have opportunities to participate and win. 2. Multi-algorithm balance: ZPoW allows miners to choose different algorithms for mining; if a particular algorithm is dominated by large miners, its difficulty will increase and rewards will decrease, allowing other miners to choose less competitive algorithms, resulting in staggered mining and avoiding all miners crowding into the same track while being suppressed by large miners. 3. Reward mechanism optimization: SCDO considers allowing even miners who have not yet generated blocks to accumulate over time (for example, providing computation proofs to increase the success rate for the next attempt). This means that small miners' long-term efforts will also increase their block generation probability, rather than relying solely on instantaneous computing power luck as in traditional PoW. 4. No pre-mining + community activities: The official did not reserve any mining slots; instead, it encourages early miners from different regions and abilities to join through genesis rewards, community incentives, etc. These measures enhance the breadth and enthusiasm of mining participation. Overall, ZPoW makes SCDO mining closer to an ideal state of universal participation, resulting in a more balanced distribution of network computing power, thus enhancing the fairness and health of the entire system.
Question 26: How does ZPoW consensus perform in terms of energy consumption and efficiency? Is it more energy-saving than traditional PoW?
Answer: Compared to traditional PoW, ZPoW shows improvements in energy consumption and computational efficiency. By introducing scientific computing-type algorithms, ZPoW avoids the waste of purely repetitive hashing, resulting in higher utilization of actual processing power during the mining process. This means that under the same security conditions, ideally, ZPoW consumes less electricity when generating blocks with the same level of security. At the same time, ZPoW reduces the demand for high-energy-consuming dedicated mining machines, as ordinary hardware can also participate, potentially reducing the energy invested in pursuing extreme hash rates across the network. According to community tests, SCDO's network has significantly lower energy consumption per unit of computing power than the Bitcoin network. However, it should be noted that ZPoW is still fundamentally a PoW mechanism, and miners inevitably need to consume electricity for work proof, so absolute energy consumption will still rise with the growth of the total network's computing power. It is just that under the same security conditions, ZPoW's design is more efficient and energy-saving. The SCDO team also places great importance on environmental protection and will continue to optimize the algorithm to make computations beneficial (for example, potentially introducing tasks that help scientific research calculations in the future), thus allowing energy to be utilized more effectively. In balancing PoW and energy consumption, SCDO performs relatively friendly, but investors and miners still need to pay attention to electricity costs and carbon emissions.
Question 27: How does SCDO's consensus mechanism prevent security threats such as 51% attacks?
Answer: SCDO significantly increases the difficulty of launching a 51% attack through the special design of ZPoW. In traditional PoW, if an attacker possesses over half of the total network's computing power, they can continuously produce a private chain, thereby enabling double spending or rewriting history. In SCDO, firstly, the multi-algorithm mixture prevents attackers from simply monopolizing a single algorithm. If the ZPoW framework provides up to 10 computational targets, the attacker needs to achieve more than half of the power across all targets to continuously win new blocks, which effectively magnifies the attack difficulty by an order of magnitude (for example, 10 types of tasks increase difficulty nearly tenfold). Secondly, SCDO miners come from a broader demographic, resulting in a more uniform distribution of computing power, making it even harder for a single entity to obtain the majority of the total network's power. Furthermore, the SCDO network has a fast block generation frequency and shard parallelism, requiring attackers to control multiple shard chains simultaneously, increasing complexity. Additionally, if a suspected attack occurs (such as a shard experiencing abnormal block generation for an extended period), the community and development team will intervene promptly, alleviating the situation through node upgrades or parameter adjustments. Overall, ZPoW significantly reduces the likelihood of a 51% attack through its algorithm balancing mechanism, making it difficult for attackers to maintain an advantage even with massive resource investments, thereby providing SCDO with a stronger anti-attack capability than traditional PoW.
Question 28: Does SCDO's consensus algorithm adopt a mixed approach with various mining algorithms?
Answer: Yes, a key feature of the ZPoW consensus is the multi-algorithm mixed mining framework. Simply put, the network sets multiple different types of computational tasks as proof of work, each with its own target difficulty. Miners can choose any of the algorithms to calculate their work. Some algorithms may favor CPU calculations, while others are more suited for GPU, each with its strengths. The dynamic difficulty adjustment mechanism ensures that all algorithms have balanced block generation opportunities: if a certain algorithm generates too many blocks due to a cluster of miners, the system will increase its difficulty, making other algorithms relatively easier to produce blocks, encouraging miners to shift. This model, resembling a “multi-mining algorithm parallel race,” ensures that no single computational track is monopolized. The algorithms currently implemented in ZPoW include matrix computation, scientific function computation, etc., and others can be added in the future. Miners can even attempt multiple algorithms simultaneously to improve their chances of winning. The benefits of hybrid mining include enhanced network security (multiple algorithms make it difficult for attackers to manage all) and increased decentralization (miners with different hardware specialties all have their roles). This is one of the major improvements of SCDO's consensus mechanism compared to traditional single-algorithm PoW.
Question 29: How does the SCDO mainnet connect with the sidechain in terms of consensus?
Answer: The SCDO mainnet and Stem sidechain have an independent yet interconnected relationship in terms of consensus. The mainnet adopts ZPoW consensus, maintained by global miners, ensuring its security and data immutability.
Each side chain can choose a consensus algorithm suitable for itself, such as PBFT (Practical Byzantine Fault Tolerance) or PoS, to achieve internal consensus within the side chain.
This means that block generation for the sidechain is determined by the nodes of the sidechain based on the sidechain's consensus, and transactions on the sidechain are not directly verified by main chain miners.
Nevertheless, the main chain supervises the side chain through smart contracts: the side chain must periodically submit state hashes to the main chain, effectively filing the latest state of the side chain with the main chain.
Main chain miners will pack this hash into the main chain block, making it irreversibly recorded across the network. In addition, if disputes arise, anyone can submit side chain transaction data for verification (challenge) to the main chain, where main chain miners will adjudicate correctness.
Thus, the main chain consensus provides ultimate security endorsement for the side chain: even if a certain side chain's internal consensus may be weaker (such as PoS being controlled by a minority), attackers cannot alter its final state and evade main chain supervision.
It can be said that the SCDO main chain and side chain form a main-sub coordination consensus system: the main chain maintains the global trust root, while the side chain operates independently and efficiently but must periodically report to the main chain to earn trust across the network.
Question 30: Will SCDO adjust or upgrade its consensus mechanism in the future?
Answer: As of now, the SCDO team has no public plans to switch the mainnet from PoW to other consensus mechanisms; the mainnet will continue to adhere to ZPoW consensus to maintain the advantages of decentralization and security.
However, the team will upgrade and improve the implementation of the ZPoW algorithm as needed, such as adding more types of computational tasks, optimizing the difficulty adjustment algorithm, etc., to further enhance efficiency and security.
On the other hand, SCDO has already provided a pathway for compatibility with other consensus mechanisms through the Stem sidechain—such as implementing PoS or PBFT on the sidechain to adapt to specific application scenarios.
Therefore, it is unlikely that the main chain will easily change its consensus mechanism, as this relates to the fundamental attributes of the network, and the current ZPoW is operating stably and securely.
If better consensus solutions emerge in the blockchain field in the future and are validated, the community and team may discuss their introduction (for example, as a sidechain or expansion module).
However, in the short term, the SCDO mainnet will maintain its established ZPoW consensus and continue to optimize. Any performance improvements will prioritize downward compatibility and a smooth transition based on security and decentralization, without recklessly changing the core consensus.