L6 - Blockchain Interoperability | by Aditya | BlocSoc Lecture Series

Transcript

so hello everyone welcome to the lecture six of blockchain lecture series uh so this lecture we'll discuss about blockchain inter or basically cross chain messaging and bridging so let's start with the lecture so what is cross chain internal Varity so uh basically cross chain internity enables us to communicate with between the blockchains uh it allow us to send messages between the blockchains and assets with between the blockchain basically in the short Parts it allows us for the B efficient communication and handling of various types of uh programs and contracts between various blockchains so a basic application of CR

inity is CR Bridge question Bridge is a type of protocol which allows you to transfer your assets between various types of l1s l2s and other types of things which are not Abed together so by assets I mean your tokens your nfts and all so why cross chain bridging is needed so basically when all the blockchains are made uh all l1s and l2s they are made such that their consensus algorithm allow them to only work inside of inside of a particular chain so if you are willing to operate inside of a particular chain you will face no

problem to send assets to other addresses and all to send your nfts and all but whenever you will try to send your asset between different chains between different L1 or L2 or now even LC you will face problem because no native form of advancement or a technical aspect has been considered while developing a consensus so consensus specs of any blockchain do not have native support for clch messaging and transfers and all so that's like blockchain and blockchain communication technology is currently highly needed to engage seamless communication between the chains so how do they

work so uh let's uh like uh there is a uh cross chain Integrity in Cross chain Integrity there are two things to consider the first one is cross chain messaging protocol and a subset of cross messaging protocol is cross briding so we will first explore how cross Bri just work and then we will D into a higher deeper St called as cross messaging protocol the basic idea behind a cross B is the interlocking and enabling of assets across various St so basically uh if you want to send assets between different chain a smart contract will be deployed on CH and a smart contract will also be deployed on CH B uh smart

contract if you want to send your asset from chain a to chain B smart contract will on chain a will lock your assets on chain a and it will unlock your assets on chain B we will discuss this bridges in deeper because this can be considered in three types further so this native form of CR Bridges can be can be classified further into three types lock and Min burn and mint and lock and unlock so lock and mint uh basically uh if you want to send a asset from chain one to chain two or chain a to chain B so smart contract or chain W will lock your asset on chain a and will deployed a red version on an

asset on chain B and we Min this red version to a wallet on chain B this is a form of Lock and Min architecture uh second architecture is called burn and Min so basically in burn and mint the contract on chain a will burn your asset and the contract on chain B will mint your asset so same asset gets burned and minted on different uh things the third form is lock and unlock so basically uh it's similar to burn and me but basically it will not burn a uh already generated asset or me a new asset it will just lock already generated asset on your chain a and it will unlock the same asset on chain B and this is how a cross

chain which will work in three different forms now uh as you can see uh when a applic when a action has been done on chain a uh and then action is followed on chain B so chain B has to know whether this action was completed on chain a or not so you we can see here that cost chain bridging is basically a subset of a higher level protocol called as a costain messaging protocol the cost chain messaging protocol not only allows you to send your assay but also allows you to send different RS of uh messages such as payloads data packets and all in the form of call data and uh this is a

higher form as compared to cross bridging now we will explore how cross messaging is currently conducted in various types of protocols and how are we going to uh make it more advanced so that uh the user experience becomes more seamless So currently uh uh from my research I have listed five of the top uh cost messaging prots which exist now this messaging Protocols are widely used by various application layer protocols to enable cost messaging inside their daps and application layer so the first first one is the inter blockchain IBC inter blockchain communication IBC uh this is the

foremost and the most earliest form of question messaging protocol developed and currently still it's the most advanced form because it leverages the cosmos stack for uh intercommunication uh recently launched a ccip which is also a very good stack for cross communication and the most advanced cross messaging is currently done by layer zero uh we will uh discuss all these things in the upcoming slides and apart from that uh there is a general message passing body which is made by excela and there is a bomb holes Bridge which uses ZK technology for question messaging and briding so we we considered three types

of cross Bridges earlier which is according to the architecture they followed lock and mint burn and mint lock and unlock and all but uh to classify cross chain messaging protocols we need a broader types so so uh to understand this classification let's consider an example for example Lis want to send a 5 SDC from chain a to chain B so first uh she will initiate a transaction on chain a uh then sh has to communicate that the transaction has happened on chain a to chain B and then chain B will uh initiate the transaction which has to be conducted on chain

B uh for example uh LS1 to uh uh burn asset at a from a vault at chainway and mint this asset on a vault on chain B so it will follow the same example asset this will mint burn asset on chain a and then a message has to be delivered to chain B that alysis asset has been burned on chain a and then chain B has to act when this message has been passed so uh to classify the cross chain messaging protocol the main distinction lies how this message is passed from chain a to chain B so uh the first and the foremost method is the method of

external validators there are external validators which who continuously monitor the network and they verify whether uh the proper action has been taken on chain a and if the proper action has been taken on chain they convey to chain B that the action has been already done on chain and you can proceed with your action to complete transaction the second method is the transfer of complete blockchain data uh block data and trans C has from chain a to chain B so that there is no need of external validator and chain B can itself conduct its own verification to see whether the action on chain has been completed and then proceed with its own action so let's uh discuss these types

in more detail so let's consider first this external validator so this is same what I have told exal validator concept lies on the external validators to verify the data uh on uh origin chain whether the particular action has been conducted or origin chain or not and then the valid data after validating this data they convey to chain second CH that the the action has been performed and you can proceed so in exter validators uh category there are three further classifications or or not classification we can say three further types of application which are currently being

used in making question Bing protocols the first one is centralized Bridges so we will discuss the like what happen in centralized Bridges is that let's take an example of warm hole so warhole contain external network not Network individual validators which validates the action on between chains and then they convey their validation result to the T the next Target chain so in wall Network this validators are called as Guardians and they called a signal called as vaa which is the aggregated signal uh aggregated signature and this signature is passed to Target chain and uh the

target chain then verify whether the signature is correct or not but the problem with this architecture is that we are relying on an external validator called as guardian if this validator is malicious then uh chain B can be trigged into uh considering that a particular transaction has occurred on CH even though it has not and this compromises the decentralization of the network so to so to improve on this as further method was developed called as uh the middle chains so middle chains dwell on the concept of centralized Brides only but what they do is they create a network of validator so not a single validator basically they deploy their

own chain uh for settlement uh for so let's consider an example of seller brid Sellar Bridge has deployed its own L1 called as state Guardian Network sdn so this is the network of validators so what this network do is that uh you can deposit your assets in the in the new settlement layer and the validator in this network uh verify you particular user transaction using voting which is token based voting they use a seller coin on this network and if the 2/3 of the votes has been passed they pass the signature and then the second transaction can be

commed on any chain because the previous chain sign signature already be passed by the validators the problem with this is that there will this this model will face two types of problem for example if the number of validators are low in this middle chain then again we will be post with centralization thisis and second is the when the token liquidity is very low for example in the current seller Bridge we can see that from the data there are only 20 validators and the seller token liquidity is about 120 million so if we considered about 1/3 which is the 36 million around so if any of the validator has access to 36 million of

the seller B tokens he he or see can directly commence of your attack um majority attack so this is the problem with midle change concept so the next protocol which was designed was the bonding protocol uh Bond protocol we can consider example of half protocol here so in bonding protocol uh user incentivization has been considered in place of validators and whenever a validator is violates their condition they are posed with the risk of slashing so basically in h we call this validas the B the bond is supposed to stake some of their assets

uh for before the stake their assets and bond is responsible for verifying the communication between chains for example Al has sent a transaction from arbitrum so wonder will see whether this transaction has been committed successfully and then it will tell to etherum that this transaction eum has been conducted you can deposit Alis transis assets in the wallet on etherum chain and then the etherum will cons mechanism will deposit the assets on the LSS wallet and etherum chain so so this is a slashing basic slashing and taking mechanism used by The Hop protocol or

bonding protocols so yeah this was the first method called as external validas now let's move to the block headed and transaction Pro so what happens in Block header and transaction proof is that uh we are not depending on external set of validators to convey messages from one protocol to another because they posesses decentralization disc so instead we take approach of light CS so in simple words what are light CS light CS are not a simple while lights are not full fed nodes well light just take data from blockchain and locally verify it uh they are not run by anything anyone

anyone can run them they just take data from all and then verify them on you and for so basically light is a lighter version of full notes they do not have to download complete data and are responsible for maintaining n they are just verifying the data yeah so the best example of light clients is uh the IBC protocol which I discussed earlier so let's discuss how this I protocol uh works so you have your chain a and chain B so chain A's light Cent will be deployed on chain B and chain

B's light L will be deployed on chain a so for example a transaction has been happened on chain a so this transaction data will be passed to the delayer and a Markle proof of this transaction will also be passed to the relayer relayer has this transaction in the form of packet and a maral proof of this transaction as well now what will happen the this light PL of CH which is deployed on chv uh this will this will receive the data packet and Markle proof from the reler and light client of CH is responsible for tracking changes on CH so it will see

this it will verify this Merle proof by considering a commitment has from the block of chaining and if the light kind of chain comes to a conclusion that yes the transaction has been successfully happened it sends a message to like it's deployed on chain B only so chain B knows that chain chain a is light has successfully verified the data the chainb will commence with its own part so this is how light Cent architecture work so the main problem of deploying uh like main problem of FL C architecture is that the deploying of flight client is very costly like uh this is the IBC light Cent uh it basically works on tender architecture

tender like only on those chains which are developed using tendermint client so for example there is a cosmos chain or Tender chain and the eum so and we want to do a communication between these two chain so for example a transaction has to be sent from Cosmos to etherium so a light client of eum need to be deployed light cent of Cosmos need to be deployed on ethereum and this lightline uh will be responsible for validating the transaction on Cosmos so for example the cosmos chain has 100 validators and the light CL which is deployed onum will be responsible for validating transactions from all these 100 validators and it's

each uh varification is done using ed1 15599 signature scheme and the verification cost of ed1 1559 signature scheme is about 500,000 gas on eum so if 100 100 validator signature schem need to be verified so about 5 million gas would be uh required to just validate a single transaction which is commun communicating from Cosmos to eum so this is not visible uh the light architecture between Cosmos and eum because eum does not have have a precompile of Ed 5591 signature directly in built in the consensus so light architecture can be

used efficiently between only Cosmos chains which are developed using tender St so this is the like architecture which is used for communication between chains so this was all about crost chain messaging and crost chain bridging protocols now what is the current researches which we are doing in this space uh the next part of this will be or the next page will be the chain abstraction chain abstraction is basically in simple words there will as you can see there are thousands of l2s and l3s coming right now L1 as well so main goal of chain abstraction is there will be no chain at all everything will be will be unified and user don't have

to even know about that assets are transfer between various types of things for user from users perspective it will be a single usdc Co traveling around anywhere so I will discuss briefly very few approaches which are currently being considered for developing same obstruction in the blockchain industry yeah so near near approaches currently like what near does does uh near has uh like near has enabled their nodes to uh understand the signature of various evm and non evm chain through multi party computation

scheme so basically in here you have a single account and through this single account you would be able to uh yeah so near so basically you will have a single account and this single account will be responsible for generating signature which will compa which is compatible on various types of chain and no the nearest native notes will be

responsible for aggregating this signature and understanding this signature scheme using multiparty computation and once this signature has been generated a single account will be able to um communicate with transactions to various types of chain MPC MPC is the current architecture utilized by DM and the second one is polygon's aggregation layer the aggregation layer went live currently recently only 3 to four days back so polygon segregation layer basically relies on the fact that all the chains which are used which are developed using the cdk cross chain development kit would be able to use a unified Unified layer for

communication uh this Tex stack basically Aggregates the GK proof across all the chains built using cdk and aggregate them and submit a unified proof on the etherium Chain so GK proof agregation is the basic concept inside of polygon segregation layer which bring inity between the chains which are develop using polygon CD optimism super CH utilizes the same concept as the polygon's aggregation layer it brings inability between the chains which are developed using op stack and instead of the ZK proof agregation op stag depends on the optimistic proof aggregation between all

the chains which are developed using op St yeah so the foremost concept is the Omni chain network uh Omni chain network is the current research going on in the inability space basically the particle network has uh developed the Omni chain framework so uh inside Omni chain you have a separate chain which will which is responsible for settling all transactions which are condu currently going on other chains so in partical network you have a universal account and a universal liquidity layer and everything will be utilized from this account and liquidity liquidity layer across various protocols so the

liquidity fragmentation is currently solved using om chain Network uh so this is the briefing of current for metods uh currently going on so in near near is life op chain is in concept pH polygon ation layer went live few days ago and particle network is in testet development so the primary offering for near is account aggregation using MPCs op op and polygon will be only focused on their own native El to and particle network will be uh it's basically Universal settlement lay like a separate consensus mechanism for all things to settle the transaction uh near will cover all

chains particle will cover all chains op and polygon will be only focused on their stat and the primary method has also been dis here yeah so chain obstruction uh is the final and the four more steps which we are currently trying to achieve in the blockchain space so uh basically let's take an example of chain abstraction like you have a wallet you have 100 usdc and you need to send like you have 100 usdc uh even though there are 30 usdc on etherum 20 on arbitrum and all but the user will never know how this

distribution is conducted user will just see that his wallet contains a 100 usdc account balance and or she can send it to anyone uh and he she does not have to worry about any chain this is basically the concept of chain abstraction and trying to yeah thank you