Proof Of Capacity

An Interesting Contender In The World Of Consensus Mechanisms

Recently, there has been a growing interest in alternative consensus mechanisms for blockchain networks. One such mechanism is called "proofs of capacity" (PoC). PoC is an algorithm that uses a large amount of memory, or "hard drive space," to secure a blockchain network.

The basic idea behind PoC is that miners must demonstrate that they have a certain amount of memory available, which is then used to store a large amount of data called a "plot." This plot is used to solve complex mathematical problems to validate transactions and create new blocks on the blockchain.

One of the critical advantages of PoC is that it is much more energy-efficient than traditional consensus mechanisms such as proof-of-work (PoW). Because miners are not required to perform complex calculations constantly, they can use less energy and still secure the network.

PoC is also more decentralized than PoW, as it does not require specialized equipment or a large amount of electricity. This means more people can participate in mining, leading to a more decentralized and secure network.

However, there are also some downsides to PoC. One of the main concerns is that it can be vulnerable to a "nothing at stake" attack, where a miner can create multiple conflicting blocks without penalty. Additionally, it can be difficult for small miners to compete with large miners with access to more memory.

Despite these challenges, PoC is an intriguing alternative consensus mechanism that has the potential to improve the energy efficiency and decentralization of blockchain networks significantly. As the technology continues to evolve, it will be interesting to see how it is adopted and integrated into various blockchain projects.

Introducing Subspace

Subspace is a fourth-generation blockchain infrastructure protocol that aims to allow web3 to reach the internet scale using an innovative and highly decentralized protocol. It will enable millions of node operators, called "farmers," to participate without staking any tokens. Instead, they pledge segments of their disk space to be used by the network to store past blocks. 

The project is built on top of the Substrate blockchain development framework, written in Rust, and positions itself as a robust base infrastructure layer for other blockchains. The team is actively working to implement their solution to the blockchain trilemma, which is the claim that no blockchain can sufficiently achieve all three of security, decentralization, and scalability.

What’s The Novelty?

• Security: Subspace starts from a Proof-of-Capacity (PoC) consensus protocol called Spartan, which is more eco-friendly and fairer than Proof-of-Work (PoW) and Proof-of-Stake (PoS).

• Decentralization: Subspace extends the PoC consensus protocol of Spartan to a Proof-of-Storage of the history of the network, with farmers who store more pieces of the blockchain's history being more likely to be elected to produce the next block.

• Scalability: Subspace leverages myriad scalability features to prevent blockchain bloat and oversaturation of transactions, including Prism scalability proposal, Free2Shard design, and Taiji fast confirmation protocol.

Subspace's architecture enables true mass-scale decentralization of block propagation, incredibly cost- and speed-efficient transactions, enormous opportunities for interoperability, and a usable infrastructure layer for data-rich dApps with substantial storage requirements.

Early Use Cases

• Subspace offers a public testnet called Aries and will soon release an incentivized testnet called Gemini.

• The project is archiving all blocks across the Polkadot and Kusama ecosystems to showcase Subspace's storage capacity and the benefits of storing blockchain history. Subspace plans to integrate with and support the Ethereum ecosystem next, with Avalanche, Cosmos, and Near likely coming after.

• Many aspects of the project are still in development and testing, including the blockchain's central token mechanism, Subspace Credits (SSC). SSC will be used to pay for storage and compute fees on the network and will need to be staked to run an executor node but not a farmer node.

• The team is also building an infrastructure portal called Subspace Meta Services (SMS) for web3 builders, which will expose a variety of Subspace's features in a more developer-friendly way, including a unified chain history API, a chain-agnostic NFT storage service and a cross-chain asset exchange protocol.

Final Thoughts

Although less popular than the PoW and PoS consensus algorithms, PoC removes the problem of cryptocurrency stockpiling in PoS and dramatically reduces the high computation energy used in PoW. The computing and crypto world has begun to realize the importance of being environmentally conscious. With the advent of the proof of capacity consensus mechanism algorithm, we can be assured of a more accessible, faster, and greener means of mining—possibly the greenest yet.