Bolt Protocol: Instant Transfers on Ethereum Mainnet – Lorenzo Feroleto,Nicolas Racchi

protocol instant transfers on the ethereum mayet please welcome Lorenzo faletto and Nicholas Raji Round of Applause please hi everyone so I'm Nicholas and this is Loreno and we want to introduce you bold which is the first proposer commitment protocol on ethereum so uh let's first start with a quick overview of how ethereum works today so um if you want to buy an NFD or a a token or anything else uh you will notice that your transactions take quite a few seconds to to actually settle and give you a confirmation um bolt aims to change that with instant transfers so uh right now ethereum has a single uh what's leader consensus mechanism which mean basically is a big word for uh something that um something simple that only one validator at a time is choosing the contents of a block uh so in ethereum there are more than 1 million validators right now uh but only one of them every 12 seconds gets to actually publish their block um this is what we call uh proposer Monopoly power uh the proposer is the term for the validator when they propose an actual block and the Monopoly is because they're the only party that actually makes any um decision into where they should include or exclude some trans transactions or the order of which they actually include the the transactions um I want to also stress that uh when you send a transaction normally you don't send it directly to uh uh validators but you you send it either to uh a network which is commonly called mol or to uh private parties such as block Builders normally when you interact with a wallet you don't even notice this but uh we need it for context on we're going to explain later in each commitment which makes them uh credibly um uh without trust so you don't need to know the proposal that you're asking to um we also have a mechanism to trustly uh figure out if the proposer um actually was uh fulfilling the commitments or not so this is the very simple schematic of uh what we mean as a user you talk to the proposer give them a tip and receive a promise of inclusion or a promise of something back and in the with Vault you can not only speak to the next proposer in line so the one that's going to build a block in like 10 seconds or something like that uh but also in uh in the next 32 slots so that's about a few minutes ahead so you have uh something that we call a a look ahead window of a few minutes in the future um as I mentioned bolt is a proposer commitment protocol meaning that you can ask the proposers whatever uh it doesn't have to be a transaction inclusion or uh something in particular um and it allows uh users to communicate directly with proposers Loreno so um what can you build with BS the biggest biggest example is prec confirmations uh pre prec confirmations are a type of proposal commitment where as we have uh we have seen before the proposer is going to commit to includer transaction and this commitment is backed by an economic value if it doesn't behave well if it misbehaves it's going to get slashed so it's going to lose some money and why prec confirmations because with prec confirmations you can actually send if or c20s or nfts or Min them transfer them without instantly in let's say 200 milliseconds without waiting for like six seven or 10 seconds like uh like usual minet flow and how this happens as a user this is completely abstracted way for for you you're going to just to receive like a quicker feedback that your transaction is going to has been executed successfully uh but uh your wallet in the background we're going to send a request to the next proposer in line running bolt and it's going to accept your commitment if you pay a reasonable tip and it's going to include your transaction the the idea the vision here is to experience ethereum like as fast as a as a rollup like arbitrum but leverage main net liquidity so a question is I've mentioned it transfers or rc20 is transfers but transaction be prec confirmed uh the answer is quite delicate it's it's a bit on the no side uh because in general we can only guarantee like um inclusion um and successful execution for transaction that cannot be invalidated by other users so for instance in the context of each transfer upon some basic checks like you you have enough balance you have enough if on your wallet you can just send your transaction get prec confirmed and it cannot fail but that's not really like the case for swaps because uh let's say the next proposer in line is in three blocks and I going to sending a swap and it's going to prec confirm it but what could happen is that price can change and as such my transaction could fail due to sleep tolerences on dexes but so we we have said that you could make deal with proposers but why a proposer can make a deal with you where it's going to say okay your swap is going to execute successfully um actually that's a bit complex compared to uh if transfers as we said um because uh suppose um the the next proposal like the next blocks is going to be proposed by uh proposal running bolt then uh since it has Monopoly Powers um over the contents of a block it could place your transaction first and then it cannot fail because no transaction before yours and ethery this works but actually uh the proposal might not be incentivized to do that and why that's the case because uh in ethereum blocks usually the top transactions in a block are mainly like sex Dex Arbitrage that are really high value so the proposer is incentivized to uh keep those on top of the Block in order to profit more from its activity and such is hard to say as a user I'm going to give you a tip to successfully execute my swap because the proposer doesn't really know if it's enough and uh we don't want B proposers to be like super sophisticated in which software they run or which logic they they operate we want to keep the the network decentralized as possible and as such we best think that this offer to first um to First offer pre-confirmation just for a subset of transaction which is still really relevant because most of the time we are just like sending assets which are uh transaction that cannot fail but the question Still Remains can can we build like a defi protocol powered by prec confirmation in uh in our opinion like the answer is is yes uh because prec confirmation will enable like a fasty x and leverage uh ethereum main net liquidity so for ex for example existing protocols could be improved uh think of a landing protocol where like operation like lending and borrowing could be prec confirmed because there are there are non contest they're not going to fail and also that that's the case for depositing and borrowing in in stable pools like usdc or usdt and also we believe that uh with the new with this new privative that's coming to live to main net in the next months uh apps will be like incentivized to build with this new primitive in mind to offer like a better user experience to you to to users so there's going to be like competition incentives to do that so back to n thank you so uh in ethereum right now there is a concept called PBS and uh basically it means that proposers uh validators don't normally build all the transactions and decide the sequence of them by themselves but they outsourc this task to someone called block Builder uh you might have heard of names like uh Beaver build or Titan but that doesn't matter basically there are companies um specialized in building the best block possible with the most value possible every 12 seconds and serve them to uh the proposers that just have to accept them and with bolt we actually um extend the API so the interface that uh these uh block Builders use in a such a way that proposers now can uh show to block Builders hey I committed to a few transactions to including them in in my block when I'm scheduled to propose and so um Builders will have to comply to those commitments this is really cool because uh it doesn't add any trust assumption any trusted party checking if they're doing everything right it's all uh based on proofs um I'm going to give you a very short uh overview of of how it works uh there are a few components but basically the the gist of it is that validators will have to change their setup with a new component that we call Bol side car uh a side car is an extra uh software that validators will have to run alongside their beon node and validator node and uh we also modify uh with the with the red arrow a few apis that makes the make this happen so uh regarding assumptions as mentioned as niiko mentioned we try to be as trust as possible so uh we are not no introducing no new in interment are introduced both is completely trust us because proposer proposers in order to offer these commitments need to post some collateral take some collateral and in case they misbehave this is going to be slashed and uh also transaction inclusion is uh cryptographically proven and we can leverage the native etherum data structures for that in particular mer patri 3 and their inclusion proofs and lastly uh if a proposer misbehaves there is like a fully on chain mechanism for for attribution like for for rollup for stage one rollups um which runs optimistically so it greatly reduce costs because it doesn't need to be verified upon sending on transaction at the end we want still like the same ux and the same cost almost the same cost for users let's give like a quicker overview how it works under the hood so uh in case a proposer misbehaves as a user you have a commitment that you can like post into a smart contract by opening a challenge and the proposer has like a Time window where it could uh dispute The Challenge and uh eventually resolve it if the transaction was actually uh included and the the the proof of inclusion consists of a micr parti three of the transactions three so uh transactions in inum along with other like type of data are grouped in this uh data structure called micro Par 3 they can give you some proofs of inclusion of certain data very cly and uh the the root the ash3 root of uh root Ash of these transactions three is post on ethereum block headers so if you go to atos scan and check a block you if you see the field transactions route that's what we're referring about and if the proposer doesn't respond in time because it is it has misbehaved or provides an inval the proof uh it's going to get slashed oops but yeah uh thanks for listening and tuning in uh this is B protocol and we are chainon a research and development field working on ethereum infrastructure so there is like the old e for