Tezos Stack Exchange is a question and answer site for users, experts, and developers of the Tezos blockchain project. It only takes a minute to sign up.
Sign up to join this community
Can users' funds be blocked on the rollup? If for example the rollup operator decides to withdraw their 10k xtz staked, does it automatically withdraw all the tickets to the L1 SC that issued the tickets? Is there always a L1 implicit address for each user to withdraw to?
Question from Greeneye44, he agreed that I can post the question.
Users’ funds can be blocked on the rollup in case of a bug, just like funds can be blocked today on an ill-defined smart contract. However, Tezos rollups are decentralized: if the rollup operator decides to withdraw her stake, this has no effect on the rollup itself (its state and the tickets it owns are not affected). Another operator will be able to make the rollup progress. To withdraw a ticket from the rollup, the withdrawal must have been performed in the rollup first by pushing a message in the rollup outbox. This message is a call to a smart-contract passing the tickets as arguments. Anybody can trigger this smart-contract call. Then, it is up to the smart contract business logic to decide how tickets are moved back to a given L1 implicit address.
The gift and the curse of rollups is that you must have one honest operator. If that operator leaves, someone else must take up the post.
This is a good thing. Your funds will still always be governed by the logic inside the rollup code & enshrined in the L1, which will never go down.
So yes, an honest node must come up and post bond + a commitment to the main chain that states you are withdrawing your funds back to L1.
If a rollup operator withdrew their stake, they would simply no longer be able to advance the state of the rollup on L1. If no one advanced the state on L1, then no one can withdraw. However, the idea is that for big rollups, multiple parties will stake and independently validate the rollup. For example, imagine a big MMO game operated as a rollup. Once they reach a certain size, guilds might want to pool money to operate their own rollup validator, keeping everyone else honest, including the game devs. This all holds in principle for other rollups, but in practice, many Ethereum rollups use a permissioned set of validators. Tezos SORU rollups are permissionless - anyone who can raise 10K xtz can protect the rollup.
