This is the 4th and final part of our series of blog posts explaining various blockchain scaling solutions. Check out the first three parts down below:
- Introduction to Blockchain Scaling Solutions
- Blockchain Scaling Solutions Part 2: Sidechains
- Blockchain Scaling Solutions Part 3: Rollups
In this final post, we’ll be discussing a blockchain scaling solution that has already disappeared into dust. In August 2017, during Ethereum’s biggest rally and hitting all-time-highs, the first version of Plasma paper was released promising a 2nd layer solution for Ethereum. So, what is Plasma scaling solution and why didn’t it work out? Let’s find out.
Plasma scaling solution is achieved by creating separate child chains anchored to the main chain and leveraging fraud proofs (similar to Optimistic Rollups) to settle disputes. These child chains can be defined as separate blockchains with their own mechanism for block validation. Thus, relying on the Ethereum main chain as a trust and arbitration layer.
It also includes the creation of limitless stacks of these child chains to offload the traffic and bandwidth congestion from their parent chains including the Mainnet. Thus allowing the developers to configure child chains to match the demands of specific use-cases.
Problems with Plasma
Well, let’s start with the security. Even though it made big promises about its security, it posed glaring holes in its security. First of all, the participating users in Plasma had to monitor and verify all the transactions on Plasma chains to keep an eye on malicious operators, thus adding significant overhead.
Another major problem and probably the last nail in Plasma’s coffin was the challenge period. Meaning the users wanting to exit the funds from the Plasma chain had to wait several days. This period of a week or two was added to allow for challenges. Waiting for 7-14 days for your own funds to appear on the main chain sounds absurd and can be such a poor experience for a user.
Besides these main problems, Plasma solution was filled with various issues such as lack of computation support (Plasma chain supported only basic token swaps and transactions), delayed withdrawals, need to periodically watch the network, and more.
Hence, Plasma scaling solutions never really worked in real life. All the promises of increasing the throughput of the Ethereum network while lowering the cost per transaction never really worked out. Soon, Plasma got replaced with better scaling solutions such as ZK and Optimistic Rollups. Rest in Peace, Plasma.