The number and speed of confirmations inherently depends on the original chain and must be set at the time the chain is admitted into the protocol.
RenVM mainnet will wait for be 6 confirmations for BTC (Chaosnet, it will be 2). This obviously takes a long time and, while it’s not so bad for some use cases (lending, collateralization, etc), it’s not the best for dApps/DEXs and general UX. So, we have the concept of Universal Interoperability. This allows a third party to provide two things (in exchange for a fee nominated by users):
(a) Provide gas so you don’t need to manage lots of different tokens, just the ones you’re actually using for the dApp. (b) Provide speed by taking on the confirmation risk. The third-party sees you have (let’s say) 1 confirmation and is confident you’re not a miner about to attack Bitcoin. They come in and provide the shifted BTC immediately to complete whatever action you were taking, and when the real underlying shift finishes the 3rd party get their funds back.
Use a third-party to submit transactions to the host blockchain. This hides gas fees for the user.
Use a third-party to take on the risk of transactions reverting. This speeds up RenVM interoperation for the user.