# Post-Merge Wallet by Chang-Wu Chen | Devcon Bogotá

- Channel: [Devcon](https://streameth.org/devcon)
- Date: 2023-10-07
- Duration: 23:06
- Watch: https://streameth.org/watch/yt-QBLkJgVgg8o
- YouTube: https://www.youtube.com/watch?v=QBLkJgVgg8o

## Description

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https://archive.devcon.org/archive/watch/6/post-merge-wallet/

Crypto wallet is an entry point to onboard users to Web3, but the complexity of key management prevents the real decentralization to be realized and widely adopted. After the Merge, Ethereum is pivoting to a rollup-centric roadmap. What does the future wallet look like? In this talk, I would like to talk about what is the missing part for current wallet design centered around L2, DeFi applications, abstract account and social recovery from our past experience.

Speaker(s): Chang-Wu Chen
Skill level: Intermediate
Track: Security
Keywords: Wallet;,Security;,UX

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Devcon 6 was held in Bogotá, Colombia on Oct 11 - 14, 2022.
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## Transcript

foreign [Music] and thank you for coming to this talk I'm Chang Fong I'm talking labs and I'm talking it's a non-castew valley based in Singapore and today I'm gonna talk about the topic which is called postmoduality so before the talk I would like to ask you guys a question what is your ideal wallet I think many of you may like use metal mask maybe I'm talking or other audits so what is your idea what it looks like you don't need to have a answer a question now but it's a worthy um to think about it so let's take some time to look at uh where we are now and look back at the past the past I would like to go through some number and some observation uh from what we have right now so here is the adoption map of eastern uh of the ethereum users so we can see uh many users are distributed in North America Europe Asia and everywhere but and this user already are crypto users so how do I Define crypto users next is because not everyone use Liquid toward it but I think uh most of the people right now they just use the decentralized exchange like Finance like FTS exchange so how do we I mean turn this kind of situation so make more people to get into the crypto Valley that is the the core idea of this topic so for now there are over 221 million people uh have quick cryptocurrency right now uh this number might not be accurate just for reference if we assume the number is correct then 97 of people don't know crypto or don't have any kind of crypto assets so one day if you want to introduce the crypto wallet to your parents your friend or even your teacher how do you do that can you help them to set up a crypto Wireless in two minutes five minutes or even in 10 minutes I think the answer for now probably is no it's really hard for them to know what is crypto because the learning curve is pretty high so here are the challenges um we are facing every day if you are working as the what is company then you you will receive the feedback like this every day so people don't know what is the crypto what is the C phrase and also they don't know how to speed up the transition when the transaction is get stuck for those questions so we need to come up with some solution for the future one is how do we fix it so if we want to make the message adoption to happen crypto wallet is a important entry point for Android website users yeah so we need to fix it so how to fix it so let's recap it again so if you want to rebuild a wallet then when you when we need to know what the uh future what it looks like so uh this is a very I mean very quick question because if you think about a smart contract developer in 2018 or 2019 at that moment because they didn't sense or they didn't know there is a kind of attack called ndv attack so when you uh when you design a smart contract at late time eventually you will you're really hard to defense uh MVD anyv attack so that's why we need to know what is the future and we need to know how to design the wallet and so this is a reason this topic called possible are merge wallet so let's look at the future the concept of the endgame is proposed by vitalica in 2021 actually it's uh the goal is to scaling the ethereum for many users so we can come uh we can onboard more users to the Syrian ecosystem for the in-game uh is uh in in the article that vitalika mentioned it is private into a lower solution uh uh Centric low map what does this mean it means we can we uh today we have already seen lots of layer 2 Solutions coming up just like star net uh Edge Tech uptrunk or optimism since uh if the layer 2 is the future that means we need to have more data space for the load up so how do we have more data on the raw up so here are two ways we can do that so first we need to have more large get more larger block and the block need to be verified very easily for the line client if we can do so then we can have a large block and that is what then charting uh doing and another approach to to do this is how do we make the data smaller if we can make each load of transactions smaller then it could fit into the bigger block then that means we can get a lot of I mean transaction get into the block so in the future ideally we think that there might be a high TPS with a low fee transaction fee into the bar trans system this is important because if we look back at the history of the internet then we will find this is a kind of similar so when the internet was formed the bandwidth is a synchronized resource and it is very expensive not and everyone can afford to the internet with the cost decreasing then we can see many of many applications start to going on the internet so if you if it was in 1998 you probably don't think about what is YouTube what is Netflix but if you are in uh 2020 or into 2000 2022 then you uh you might think Netflix it makes sense we can have more uh uh online video with cheaper transaction fee we can do Morphine not just Define not just nft we can do lots of potential application in the market so yeah let's let's think about how do we make the world better so we can have more application uh on board into the Ethereal ecosystem so yeah we need to have a wallet which fits a lot layer 2 door mat and there is user is friendly here I want to give you a very brief short summary so first it's really hard for the general users to know what is crypto what's easier and think about it if you want to teach your parents to set up awarded the first thing the first thing is they need to write up the difference so what is difference yeah it's difficult to understand and then next they need to uh if they want to send some token then they need to have some easer so this is another thing that uh quite quite challenging for them because what this cannot make a trans transfer unless I got some easers the second thing is the user experience is pretty uh bad now um because I think because the learning curve is is pretty high so most of the users don't know how to I mean run the awarded like how do I interact with the device if there is a new application how do I access the application they need to learn it from the video or some kind or they really uh or it's really hard for them to know how to do that and third uh just like I mentioned uh for now we have already have some users but most of the users are not crypto user they are just general users and because of this challenge uh they are they are just uh state with the centralized exchange how do we I mean try to try to get them into the ecosystem so we need to have a layer 2 ready Wally which is designed for the future I think this is a very big thing because in Defcon we see the merge is already finished so the layer 2 is if layer 2 is the feature so we need to start to thinking about what is the future what it look like Safari is a requirement we think uh ideal what it should have it's open for I mean if you are working again if you are working as a water company this is really overwhelming every day you always uh receive a user's feedback complaining uh their token was stolen or they just make they just approved to some fake contract so how do we avoid that avoid it and even though they are more uh important important question is how do we make sure the user's assets is safe and how do we have learned to manage their key so today I'm not go off this topic but I will just focus on the key management and the how do we make their account could be recoverable here are two solutions uh one one is MPC any other is a a abstract account I think the abstract account is a very popular topic during the the account talk every day so you might probably might heard about it but for NPC who is NPC MPC actually is a multi-party computation so think about this example if you want to generate a random number you can ask um if you want to Generate random some versus three people you can ask each one to to uh for a lumber and then we can sum it up to get the results so actually the MPC is a way for jointing Computing a function over the input let's take another example uh if we can take the signature as a result we can ask each party to contribute part of its secret numbers of the input and then we can get the signature so this is kind of some movements or match Magic uh we do we do not need to have a private key but we can generate the validate signature so the input is not related to the private key so you don't need to worry about once your device got lost because there is no privacy store in the device but but eventually the signature will be generated the way it operates is pretty similar to multi-seek uh think about that if a user needs to uh request a transaction you need to have another party to come to co-work to generate the signature so this is uh really like the artistic Majestic Way to uh to send a transaction so this is a very uh important feature for the NPC wallet and the mpc1 looks like an eoa with an invisible private key besides it could be designed with the threshold settings for example like two of three so for example if we uh if this is a threshold signature then we can uh if we want to send a transaction then the device need to co-work with another device which is online together to generate the signature but also this is the uh the uh the weakness of the MPC it needs it needs the help of another online devices to working together if you think about that um for this secret which uh distribute to different devices it could be stored in some it could dedicate to some decentralized centralized service so for example if we uh if the if the service help to store this sequence then the service could help the user to identify the the transaction it's valid or not because one day if the the user wants to interact with the app or some device application once this party finds the device is fake or it's a scam then it can it can stop to help to generate the signature so it's it's more like this is a kind of like a risk Control Function and another part for the NPC is it could support multi-chan because as I mentioned the MPC only looks like an eoa with a invisible foreign key so all of the if this this is a wallet and they are all go with this invisible private key for so for mpc1 it could support BTC Bitcoin it also can support the easier and all of the uh public chain is uh layer if their signature is NPC friendly so this is a sounds perfect but for the mpcc solution just uh just like what I mentioned it requires having an online Computing unit to code work with uh these are accounts in Instagram we have these two two types of account one is eoa and the other is a small country account so I just talked about the eoa over the NPC solution so how about we talk about the control account so this is a so it's a kind of a small country warning so the nice thing lets the smart contract is it is flexible you can call anything into a smart contract so you can have a customized lure so you can Define your rule into this smart contract with the AAA wallet there is a entry entry point with two faces verification and execution because in current ECU and transactions are verified by ecta signature which parents and the nuns check and then SQ the transfer of all the core function so we need to have we need to divide this verification and the execution so this is a pretty easy for the wallet so what does is important if we can customize uh each kind of verification dual so let's mean we can Define any kind of signature that in the smart contract like POS like as you know or like eddsa so we can have all kinds of signal signature verification rule are building into a smart contract and also if we think this is not safe we can make it uh as a multi-signature wallet so that means you can control uh the Water could be controlled by five people but only three people uh approved then the transaction can be execute and then the other uh Advantage is it could be designed to verify of trend signing messages so this is pretty important because if you think about the Meta Meta transaction um or yeah if you think about a meta transaction or some gaming app because the users don't know how to get the easers so if you can have some relay to help them to relate to relate a transaction that would be useful because they don't need to buy the user when they want to send a transaction and the last is I think that is more important is we can change the signer okay to me the most important and interesting thing uh for abstract account is we can abstract account from the signer a Founder eoa so that means we can have a signer and we can have a account uh but the account doesn't equal to final so this is a very important feature because one day if we want to design a kind of application like did or so Bank token the account could be fixed and it could we can have the same address but we can have a different signer to control this account uh here is a summarize of the some part of features of the NPC world and the abstract or a wallet so for MPC uh it's developing in 2018 and then for now there are many Protocols are used uh so you can use any kind of this uh to design your NPC body for AAA recently there are some EIP like 2938 and the 23 30 statement yeah so if you if you are interested in then you can uh try to read it and the address Alice is actually is a hierarchical threshold signatures uh protocol which is designed by me and my colleague uh this is a different social signature because we can have a different asset structure trying to make lecture with a hierarchical level compare some of the important feature with the NPC and the a wallet so for MPC and and a both of them are good around in multi-stick way so that means we can have automatic multi-signature uh operation to but for AAA because the account and the sign up could be different so that means the account could be changed in the future so this is pre uh uh not account the sign up could be changed or this this is a typo okay but for MPC because the private key is equal to account and the signer so yeah this is not possible but for MPC and the AA Wireless because they they all could be designed uh with a social recovery so that both of them work with that and for NPC and the air Wireless all of them can support risk control just like what I mentioned NPC one is you can if you dedicate your sequencia to another centralized service then this centralized service could help you to uh filter those malicious operations from your users but for AA because this is a smart control wireless so you can Define any kind of lure into the smart contract like you can set the daily withdrawal limit or you can have some Wireless edges but for NPC because this is a it's more like a private key solution so it could support multi-chain but for the A1 it's because it runs on the smart contract so that means if the public chain does not have a smart contract or things or or it's not even comfortable then it cannot be support multi-chan and for MPC uh because this is not the smart contract so it could not doing some meta transaction uh so yeah for AAA it can take advantage of the meta transaction but for D5 friendly I think this is a very very important Point here so a sounds like a pretty cool thing but uh if you try to look at all of the smart contract uh development right now not every smart contract supports Smart Control body so that's mean only the eoa can control or can interact with the smart contract and also another thing is uh most people do not support EIP 2071 it's an interface for the Smart Control Wally yeah so this is uh um I think this is the advantage of MPC Wally strongly stable we can see the post and the cons of this kind of these two uh Solutions I just follow the mean from the is too much yeah Hey where's the shower I just should so shallow is here okay so yeah we can combine NPC and the air while so we can design a future wallet you can have a worry like that if you consider this is the future one then have a sign here and we can have an account into the Smart Control wallet and also uh because of the feature of the MPC and the AAA for MPC it could be long in of chain but for AAA it could be it because of the operations are on a smart contract so it should be Unchained so there are two different features but I think you can take a bit advantage of this kind of two solutions and third because uh just like I mentioned NPC needs another party to be online to help to co-work to generate a signature so it should be synchronized but for it but for AAA it could be a synchronized but this is not really friendly for multi-6 what is signature Wally because for money signology when you send a request you need to have another party to sign a transaction so there is a lot of delay so at the last I think uh if we can combine these two kind of solution this is a benefit we can design a future world for this kind of application like for payment because for payment you need to have a very user-friendly value so and for did you need to have a account uh have a address which is a sent as an account yeah so we can do a lot of things if we can combine these two kinds of solution so thank you this is my talk