HOKIE: Blockchain solutions and major layer 2 solutions

In recent years, a variety of solutions have been proposed by technology developers and project teams. These solutions can be divided into two main categories: on-chain capacity expansion and off-chain capacity expansion.

On-chain expansion is a direct operation on the blockchain -- modifying rules, including block size, consensus mechanisms, and so on. For example, the block size of bitcoin blockchain can be directly expanded from 1M to 32M, 128M or even 2G (this is the difference in block size between BTC, BCH and BSV). For example, the technology solution that is expected to be adopted in Ethereum 2.0 is Sharding technology.

Off-chain capacity expansion refers to the establishment of a second Layer of transaction network outside the main chain, so it is also called "Layer 2".

If the on-chain expansion is analogous to road widening, then off-chain expansion is the construction of new viaducts, tunnels, paths, etc.

Current off-chain expansion schemes can be divided into three main categories: one is for extended payment, such as lightning network on Bitcoin; One is for extending smart contracts; Another class is for down - chain calculations.

So, what are the relatively well known by the public chain expansion plan?

Without a doubt, the most widely known off-chain expansion is bitcoin's Lightning Network. On January 14, 2016, the lightning Network's "white paper" (paper) was published and subsequently developed and tested by a large number of developers. In January 2017, the first lightning network implementation, LND, released its Alpha version. In the summer of 2017, the groundwork for the Bitcoin Lightning network was completed. So far, the Lightning network has 10,423 nodes, 34,780 channels and 821.1BTC locked.

Of course, the current lightning network is still in the development stage, not particularly mature. In March 2018, lightning Network nodes suffered a DDOS attack that took about 200 nodes offline.

Similar to the Bitcoin Lightning Network is the Raiden Network, an off-chain expansion solution on Ethereum. Lightning networks support instant money transfers, low cost, scalability, and privacy, but the underlying protocols are complex and not easy to implement.

Liquidity Network is a competitor of Thunder Networks. The main purpose is to move transactions from Ethereum to the payment pipeline, which allows Liquidity Network users to move transactions back and forth without paying fees, just to open and close the channel.

All the above are payment extensions in downchain expansion, while hierarchical side-chain Plasma is smart contract extensions. Plasma is an Ethereum layered side chain written by developer Joseph Poon and Ethereum founder Vitalik Buterin. The main goal is to move a lot of smart contract computing to the side chain rather than the main chain.

Celer Network is also a well-known off-chain expansion scheme. The main goal is to build a universal network that runs on existing and future blockchains, allowing everyone to quickly build, operate, and use highly scalable DApps.

Up to now, there are more than 30 known off-chain expansion schemes, but they are all in the early stage of development. It remains to be seen which expansion solutions will be the first to mature and help existing public chains solve scalability problems.