Ethereum's expansion plan: Plasma's past and present (3)
In the previous article, I introduced that after the birth of Plasma, with the advent of the digital currency bear market and people's more objective and rational judgments, it gradually lost its former aura, because it brought more problems while solving problems.
In Plasma, each user must monitor and verify all transactions in the Plasma MVP chain to discover illegal behavior and exit the MVP chain. But monitoring and verifying these transactions is costly.
And once users enter Plasma to make transactions, it is often difficult to exit. Because when a user attempts to log out, he must submit a logout request first, and wait for a period of time after submitting the logout request. This waiting period is called the "challenge period". During the challenge period, any user can present evidence to prove that the user's withdrawal request is illegal (for example, the user illegally mines or steals other people's digital assets, etc.) to reject the user's request. Therefore, even if the withdrawal request is legal, it can only be executed after the end of the challenge period, which may take up to 1 week.
And the worse situation is: if there is an operator who controls the transaction data but does not make it public, and some users need to leave Plasma to get their funds back, then each user in Plasma can only The given states withdraw their respective amounts (note: to prevent fraud by malicious operators, the order in which users leave Plasma is determined by when they last had a valid transaction).
In the worst case, if all users wanted to leave Plasma, all valid states would have to be submitted to Ethereum and accepted "challenges" during the challenge period. Since Plasma has an unlimited number of users, but the processing capacity of Ethereum blocks is very limited, if all the valid states of the entire Plasma are submitted to Ethereum for processing, it will completely block Ethereum, resulting in the processing time of transactions being reduced. Greatly delayed or even indefinitely. This is known as the "mass exit problem".
In the digital currency bear market that came in 2018, followers of Ethereum began to realize that Plasma MVP technology is not as perfect as imagined, and these problems encountered by Plasma in practice are almost insurmountable, or even unsolvable. The direction Plasma is taking is considered a dead end. At the same time, Ethereum is still struggling with congestion, and Ethereum 2.0, which is expected to fundamentally solve the congestion problem of Ethereum, is still far away.
In the middle of 2018, although the price of Ethereum continued to fall, the research community of Ethereum continued to improve Plasma and iterated the design of Plasma. Finally, a new generation of Plasma technology appeared, which is "Plasma Cash".
V God is also one of the main designers of Plasma Cash. In his opinion, Plasma Cash technology has greatly improved transaction performance, and can also solve the headaches caused by Plasma. People began to be optimistic again, and even believed that this new technology could reach hundreds of thousands of TPS per second.
Before we discuss Plasma Cash in depth, let's review several types of problems encountered by Plasma MVP technology:
1) When some operators do evil, there will be a "group leaving problem".
2) Users need to wait for a challenge period before officially leaving Plasma.
3) Users must monitor and verify all Plasma transactions.
So in what ways does Plasma Cash revolutionize Plamsa, and how does it solve these problems? We will continue to share in the next article.
