Layer 2 Interoperability | Tomo Tagami, Pheasant Network | ETHTaipei 2023

so we still have an amazing section this afternoon so um it will start with a Thomas sorry the face and network is an optimistic Bridge Network inspired by the atomistic roll-ups tomosang from Professor network will give us a talk about the layer 2 interoperabilities okay so welcome Thomas okay so hi everyone and thank you so much to everyone involved in the organization Taipei it's a great pleasure to host such a wonderful conference so let me have a seat for 30 minutes okay so my name is Tomo and I'm the co-founder and CEO of optimistic Bridge called feather Network today I will talk about radio to interoperability with optimistic Bridge uh okay so before we begin uh let me share a program I had this morning uh I came to this up this venue yesterday raping my hotel Key in my room then I went back to the hotel and asked there front desk for help without the key of course I couldn't enter the room and today you know I came here again leaving my key in the room so I don't want to go back to the hotel today so what I'm trying to say is that not your keys not their coins hotel Key at the front desk like dude for us don't verify in the case of the conference okay so anyway let's start talking once again my name is Tomo CEO at Federal Network please follow me on Twitter if you like contact me and I follow you back I have been active in the crypto space for a long time and actually if it's a network is my second project uh the fourth one was the crypto blockchain education platform called Paul por stands for proof of running and you can run about crypto or blockchain and you can earn Port token in other words you know run to and like operator I launched this project in 2018 and thirdly last year then I launched with the network uh so I hope no one wants to know more about Paul then with the network because it's easier to understand Educational Service than optimistic Bridge so finally I'm also a co-founder of the Japan different Alliance my nationality is Japan but I live in Singapore because Japanese vaccination system is two strikes for crypto web3 startup yeah okay let's get into explaining the feather Network today I will talk about Radio 2 interoperability using optimistic Bridge and to this store it's a shortcut to understand how hidden works for the network is the bridge specifically designed for layer 2 networks for example you can bridge is from ethereum to scroll or optimism to ethereum uh I think you will understand better if you actually see the demo then if you're explaining explain it in words so pleasant is an optimistic Bridge so if the demo doesn't work please be optimistic okay so what you should look for when viewing the demo is speed and low gas cost and the number of networks supported so let's go okay just for moments oh oops okay so this is the front end of feather Network there are many yeah there are about 10 networks supported at this time for example or just for oh my God yes I already supported about 10 networks including optimized membrane uh this is testnet so optimism membrane arbitrans cross you can think best organ GK VM linear and yeah and you can be one of the first to try out the heart rate to in testnet and polygon optimism and arbitrum are supported as a main net so let's try the okay let's try the bridge between ethereum and scroll for example here nothing that feels very cheap yeah written okay take a look his name is Mr President I have his sticker today so if it request me of the decision if you want and notice again the very low gas costs maybe you cannot see here but and you really enjoy his unique birth while the transaction is being processed please be patient the network may be a bit congested come on hey okay it's done so and you can see the research can yeah so okay so do you remember how long it took to process the transaction yeah I gather about 20 seconds please remember that number 20 seconds okay be back the Earth right okay so let's compare to other Bridges like a hot hot protocol the reader in the bridge space charges over 20 Dollars In 10 USD in gas cost bridge 0.005 is with this Ramen optimism here is the capture of my actual attempt here yesterday please remember 12 years Dara by comparison the present allowed you to bridge for Just Two Dollars 2.09 Direct this is the power of optimistic bridge this is the actual number on the main net and next is the comparison with other Bridges from height a speed perspective with the official Bridge offered by optimism the bridge provided by Optimist states that it can take up to 20 minutes yes so you can see 20 minutes to bridge 0.005 is in contrast how many seconds did it take present in the previous demo uh yeah that's right only two seconds two seconds no 20 minutes this is a power of Weather Network and optimistic Bridge Weather Network was selected for the ethereum ecosystem Support Program stands for ESP a grant program offered by the ethereum foundation and recognition of this point super high speed and super low gas costs this is the optimistic Bridge and feden is the only project the world to be selected in the rare 2 category among the adapted in the same period uh 2022 quota free yeah now that you know the power of the optimistic Bridge let's take a deeper look at Radio to interoperability let's go so I don't need to reiterate the awarded full of blockchains there are many blockchains and although a number of Radio One chains were created between 2022 and 2021 they are in a fragmented state we need to Bridges deeper layer messaging protocol mechanism to connect them all we can run from history but Rusty was the fourth year of the latest network with the optimistic grow up developing around arbitrang and optimism when this happens what we need a Bridges amazing protocol to connect radio to Networks we don't have much time today to talk about amazing protocols such as cosmos or okay just for me and rayadero but the area is also very exciting and we have to discuss it past uh personally okay so today I will talk about three Bridge solutions for connecting the Etsy networks first one on a basic Bridge the second Decay bridge and Russia optimistic Bridge what is the basic Bridge which includes the official bridge for example provided by Optimist one dimensional earlier and the current mainstream marzick Bridge as you know our Market bridge is also known as the bang and mint Bridge the official Bridge basically supports bridging between ethereum and its Network so it cannot Bridge with other Reyes Networks so March 6 Bridges as you know notorious for the frequent occurrence of huge exploits you know so the cause of this explained in detail on present blog or fed and dogs but they are mostly human era uh the fact that the liquidity pool is managed in one place makes it an easy target for hackers to attack and the damage can be severe in the event of an outflow fund okay so next let's talk about zika Bridge the Key Bridge is a protocol that allows the specific States change that occurs in one network to be proven in the other networks by using DK snacks you know it's Unique in that a direct communication between all networks because it can prove States changes rather than application specific Community application specific communication in other words although it's called the Decay Bridge it can be applied to a methane protocol between networks as well as Bridges uh yeah there is the published Barclay research paper on zika bridge from which math can be run [Music] here you can look for JK Brad trust rescue Chain Bridge made practical by Barclay here 13 pages yeah this is a performance test table go back to the slide and the conclusion is that practical application is still in the future but the result of performance tests have been published and briefly presented here by take a bridge the table this table of performances in this paper is included this performance test was not a bridge between layer 2 but rather than more challenging like a cosmos and ethereum messaging protocol so 38 may be a little hard to see that but the performance this was conducted using 32 machines with Intel external Platinum 8295 CPU and three gigahertz with 192 gigabytes of RAM and 32 Blockheads were tested together the the results were that it took about two seconds to generate the GK proof the size of the proof was 131 bytes and the gas cost for the verification was 227k gas it's roughly 7.5 to 7.

7 USD calculated at 20 G way so my my personal impression is that neither the speed nor the gas cost is very effective for using GK for the bridge unlike the expected ticket for it to like the kbm decorora for example scroll organza kbn stock net and so on okay so finally let's look at the details of how the optimistic Bridge works when we started the project we considered whether to adapt their basic Bridge or the optimistic Bridge or the Decker bridge and we chose the optimistic Bridge the optimistic Bridge as the name suggests you know is inspired by the optimistic grow up the bridge is unique in that it handles transactions in non-optimistic way so optimistic grow up is unique in the data Roll-Ups multiple transaction into a single transaction and record it to ethereum and furthermore it only verifies if the transaction is fragment so in this way gas cost can be significantly reduces in the optimistic Bridge only the optimistic part of the optimistic rollup was adapted and applied to the bridge so there therefore it's not a roll-up not a rolled up as you can see the this diagram of this bridge implements mechanism to validate only when there is an irregularity in a bridge transaction by doing this the gas costs in the bridge can be significantly reduced other shows in the previous comparison with hop protocol optimistic Bridge only verified transaction requested by verifier called like a disputer this means that the vast majority of transactions are returned to the network without being verified so this this diagram illustrates transaction in verification validation in optimistic Bridge uh transaction is in ethereum stored in blocks this is a regular technically block header and eventually output as this technically block brokers since this harsh data it goes with a thing that changing the data will output different brokers in other words the consistency between the information is the block where the bridge transaction is stored and the information in the broadcast is verified the information contained in the blog is extensive making the cost of verification high and and with optimistic bridge and of course with optimal app the gas cost can be significantly reduced because the sequence of events is verified only when I regularly occurs this is a very simple and secure mechanism because only a block header and block hash are required for transaction in ethereum wire transaction verification in a bridging bridge between layer 1 and ethereum is a completely different process so this is exactly why with the network offers a bridge specifically for layer 2. okay so once again we compare the Three Bridges together we can cross for it the basic Bridge as verifying on chain and Decay Bridges as verifying off chain and the optimistic bridge at not verifying or more precisely verifying only in case of fraud while we can see from this is that optimistic bridge is the best in terms of the gas cost this is because the basic bridge and zika Bridge verify some transaction while the optimistic Bridge doesn't verify them in their first place so pheasants chose the optimistic Bridge because we've heard the Rogas cost and transaction speed were important in order to have a smoother bridge between layers Network for example optimism to have tram or scroll to stagnate and so so basically we believe that the optimistic bridge is Superior in every respect compared to the basic Bridge however compared to take a bridge it's inferior in terms of the bus authority so the temperature is Superior in that you can get verified transactions as soon as possible whether as the optimistic Bridge doesn't verify transaction in the first place so you can get you can get verified transaction with optimistic Bridge and therefore a GK Bridge can handle more use cases at this point however GK is still in the research phase in my opinion and there are many things missing from its application to bridge only to bridge so okay so I would like to conclude by talking a little about the future uh as you know the marching era gained gained momentum between 2020 and 2021 as a result marching Bridge gained a lot of attention in 2021 so but at the same time huge exploits became a problem you know uh last year was the fourth year of the rate as I mentioned earlier with optimistic grow up gaining momentum around avataram and optimism so and this year JK row raps are starting their Journey so as a result next year should be uh Heyday for red Bridges and president hops to submerge at The ethereum X system by connecting many layers Networks uh what we run from history then is that Bridges prone to huge exploits so bitterake has also pointed this out right see so and for them does not maintain liquidity pools in one place but rather decentralized them over multiple private keys in other words this is a decentralized liquidity pool we will make every effort to ensure that users can move the asset to Reactor with confidence networks are explained in details in dogs and our blogs please take a look if you like thank you very much for your attention and so let me make a few final announcements as you know as you all know next year's Devcon will be held in South Asia story Taiwan is not in South Asia but as we are all from the same Asian country I hope we can get the event of two Augusta together so we are currently talking about setting up ethereum Asia diagram with members of the Italian Community for example in Japan Singapore Malaysia and Vietnam so please join us if you like and finally prays for Office later if you follow us and say something please with reach out to me and I will give you your Mr patent sticker also we will we will be launching a Educational Service in the near the future where you can run about radio to stay tuned and follow us later to receive announcements sorry thank you again for your attention [Applause] that's faster one uh can you give an example of the fraud proofs that the fashion Network uses sorry can you give an example of fraud proofs in the Pheasant Bridge working for proving fraud I cannot hear you so uh uh you do a pheasant uses optimistic bridging so you have a mechanism for submitting a fraud proof fraud frock fraud f-r-a-u-d what's that I can hear okay I think his question just how to uh produce the front proof or and verify it do you have a good question yeah thank you so thank you for your question yeah so this is a very great question uh the seven day frog proof you mean is an event in the optimistic Road app mechanism the optimistic Bridge doesn't have to wait for however ethereum limits uh sorry uh the optimistic Bridge doesn't have to wait for seven days because uh Federal network is the optimistic bridge is different completely different optimistic roll up however ethereum limits the number of blocks that can be different when bridging between Radius uh 256 blocks so this means that if an irregularity occurs at the optimistic Bridge the irregularity must be noted within around one one hour about one hour so we are currently investigating the possibility of increasing this number of blocks so in conclusion if you use the federal Network or the optimistic Bridge you don't need to seven days wait seven days um hello it's the general from risk Finance um so a lot of bridging that I've seen has been from wallets to wallet on different chains and um and that's great and I saw that you had a multi-sig as well so that's also great but nowadays a lot of funds are managed um inside protocols so this could be down so this could be protocols controlled by other things um I'm really excited about what vitalik said yesterday in the morning um Layer Two to Layer Two avoiding going via ethereum but something that for me interrupt interoperability means is to be able to one contract on one L2 controlling other contracts through RPC remote procedure call on other chains so this way liquidity can be bridged and then also transacted with controlled with other protocols on other chains without needing for a user with their wallet to go through because you know when funds are inside a protocol they're locked inside that protocol that's like a core tenant of um like smart contracts in in terms of how they control liquidity um what is the roadmap um with uh regard to having remote procedure calls um and controlling bridging through a protocol