hey @sg, we are working on modifying the Truebit VM to take EVM calls, nothing that is presentable until now.
I received an interesting question via email recently, and think it is worth sharing and discussing:
It is not clear how Plasma MVP confirmation or no confirmation schemes for dealing with data availability on UTXO payments child chains extend to to general computation chains. Would you mind explaining this in more detail?
Computation in itself does not require any changes to the confirmation model. Yet, there are only very limited use-cases where computation is used in isolation. Often there is a deposit or a reward with the outcome of a computation. For example the computation executed over the course of a poker hand decides the distribution of the funds to players.
The paper proposes 2 types of transactions:
- transfer-type UTXOs hold funds on the address of a key (as in Bitcoin)
- computation-request/response UTXOs hold funds than are solely controlled by its code (DAO-like smart contracts)
Type 2. UTXOs are similar to contract accounts in Ethereum, which have no associated private key.
The no-confirmation scheme became interesting when analyzing data withholding during transaction from transfer-type UTXOs to computation UTXOs and vise versa. As there is no private key with computation requests/responses, but only the hash of the contract code, schemes that require signatures by private keys can not be used.
I understand that there are more complexities about securing funds in DAO like constructs on Plasma chains, especially as data withholding is not a discrete event, but a subjective impression. We are currently working on a list of use-cases that we think are applicable for such contracts and try to distinguish them from use cases that can not be used on Plasma chains.
I will follow up with updates in this thread, also keep an eye on our github.