What is Plasma?

As of May 2019, the market for crypto assets (virtual currency) is gradually recovering as a whole. One of the backgrounds is the various projects for real demand. In this issue, we will discuss Ethereum’s Plasma as of the one of the initiatives for real demand.


Challenges for Real Demand

As one of the challenges towards real demand, scalability issues cannot be avoided. The problem of scalability in cryptographic assets (virtual currency) is that the number of remittances (transactions) exceeds the number of minors that generate blocks (the number of processes), resulting in delays. Also, the sender can generate a block by paying a remittance fee (transaction fee) to miners, but this fee (transaction fees) can be decided by the sender himself. The miner can also decide which remittance data to put in the block when creating the block. This system makes it easy to incorporate remittance data with many remittance fees (transaction fees) into minor blocks quickly.

The number of Bitcoin transfers (transactions) grew enormously in 2017, and the processing of miners has failed to catch up, and there has been a blockage of transfers, and at the same time the remittance charges have risen. The market was in a downturn in 2018, and remittances of cryptographic assets (virtual currency), including Bitcoin also decreased sharply where remittance clogs and remittance fees also decreased.

In the case of Bitcoin, there is no problem if scalability to the number of transactions is maintained at the time of remittance, but Ethereum is a blockchain itself because there are also functions of smart contracts and Dapps in the remittance function. This is likely to be very heavy. In fact, Ethereum’s remittance fees are higher in 2018 than in 2017. The main reason for this phenomenon is the fact that projects such as Dapps are standing directly on Ethereum’s main chain.

[Reference: bitinfocharts.com]


One of the theories born there is Plasma (plasma)

Plasma is a theory proposed by Ethereum founder Vitalik Buterin and Joseph Poon who has proposed the Lightning Network. Plasma, which is expected to be a solution to the scalability problem of cryptographic assets (virtual currency), creates a blockchain separately from the Ethereum blockchain, stacks several layers of blockchains, and becomes a book chain (Ethereum blockchain). It is a theory that connects and lightens the burden. If this chain (Ethereum blockchain) is the first layer, Plasma consists the area of ​​the second layer.

* Plasma can be stacked in layers, so it is possible to form layers such as second, third and fourth layers.

【Reference: plasma.io/plasma.pdf


The idea is similar to Lightning Network. Lightning Network is processed off-chain, but in the case of Plasma, it is processed on-chain.

It also has a similar structure to Lisk utilizing side chains from the beginning. However, Plasma can stack blockchains in many layers.

Plasma is composed of a hierarchical Tree structure, when Ethereum’s blockchain is used as the main chain. With the conventional Ethereum, transactions must be processed only on the chain, but with Plasma, each time a block is added on each Plasma chain, the header hash of that block becomes the upper hierarchy.  The burden on this chain is reduced by transmitting it to the Plasma chain and transmitting only the final state of each Plasma chain to the main chain.


Security on Plasma?

【Reference: plasma.io/plasma.pdf


When transaction data occurs in Plasma, it sends transaction data to the node in the next higher hierarchy in the tree. The receiving node also sends transaction data to the node of the next higher hierarchy. The nodes in the upper hierarchy recalculate the transaction data in another lower hierarchy to verify whether it is not false data. It sends transaction data to the next higher hierarchy only for transaction data that has been verified not to be false. It is a mechanism like a message game played while inquiring various people of the answer.

【Reference: plasma.io/plasma.pdf

If a malicious node comes out, it will be detected by this mechanism. If detected, the node that issued the transaction data is notified and it is possible to cancel the transaction data. Or, you can re-send data to another non-malicious node in the hierarchy. Malicious nodes are subject to penalties. In addition to this verification mechanism, we also need a node that fully monitors each Plasma node and keeps it monitored. Even if a block containing incorrect data is generated, if it is rejected by a node that is standing up and monitoring a full node, it will be rolled back to a block that does not make mistakes.

【Reference: plasma.io/plasma.pdf



In this article, we focused on Ethereum’s Plasma, but many projects are creating new innovations every day that I cannot tell about with crypto assets (virtual currency). The author thinks that the technology of crypto assets (virtual currency) will surely enter the future world, which will become even faster in its evolution.