Bridges
ethereum 2700 dapps
polygon 37000
arbitrum 80
MetaMask makes money from swap fees, management fees, as well as by selling merchandise via its online store.
Interoperability is one of the most important requirements for an ever-changing and evolving ecosystem.
A bridge is an app that allows you to transfer assets (cryptocurrencies, NFTs, or other tokens) between one blockchain and another. For example, transferring from BSC (now BNB Chain) to Ethereum.
If you send to your Ethereum address from BSC, BSC will send to the address you put in, but on the BSC network.
For more information on this specific scenario,
You should choose a bridge primarily based on what you're trying to move, where. For example, some bridges only move ERC-20 (currency) tokens; others specifically handle ERC-721 and 1155 (NFTs). The last thing you want to do is try to transfer tokens to a different network, and never receive them.
Polygon deployed Curve, AAVE and SushiSwap
As a user, I used Polygon Bridge:
transferring tokens without interference from 3rd party agents
what is a bridge: <<sharing data and tokens across networks>>
>> bridge connects different blockchain networks to provide better flexibility for asset transfers
>> Polygon bridge V2, based on proof of stake chain,
>> trustless two-way chain transaction channel for facilitating communication between two networks
>> helps to transfer NFTs and ERC20 tokens to polygon leveraging smart contracts
- I transferred ERC20 tokens
how does it work? dual-consensus architecture for optimizing decentralization and speed
connection allows transfers of tokens from one chain or network to another chain or network, all coins have separate networks
you can have eth token on bns or polygon (representation on another chain/network)
Aave: borrowing or lending, for interest
cross-network transfer because:
ON ETH ETH>> COIN, >>ON POLYGON>> TOKEN
the prices trades the same on different network (coin, token)
aave: lending and borrowing (eth on eth 0.5%, eth token on polygon 3%)
so moving
Why bridges?
- ERC20 coins are native to ethereum, CEXs don’t sell native coins (coinbase), they sell tokens on the ethereum network >> so you don’t get the true coin
- to access new networks: switching native ethereum from native network to polygon network because of gas fees. (polygon was created to scale ethereum, but it doesn’t have the same security that ethereum does, because it is a bit more centralized)
- Progression: no one network can do everything, so bridges will allow more interoperability and ‘collaboration’ between networks to solve problems.
Issues with bridges:
- they’re a bit more centralized and not as secure. Each bridge has a team or entity or a company behind it
- they’re bit slow: transfers take minutes, hours and even days sometimes
How do bridges work:
- centralized
- extension of some exchange?
- large pools/company/person of eth tether <> polygon tether, both are tether representations on tether networks
- this company sends your tether on eth to the first pool, and send you the same amount of tether on polygon for a fee paid to the centralized authority or the liquidity pool YOU MUST TRUST THAT THE CENTRAL AUTHORITY SINCE SOME TRANSACTIONS TAKE DAYS
- ALSO you need enough liquidity in the second pool, which means you may have to wait for someone else to make the reverse type of transaction so that the token is available in the second pool
- smart contract
- the asset you send is frozen in a smart contract
- you get a copy of that token on the new network
- this is only used for coins that don’t have their own smart contract capability like (btc, btc cash and doge coin), ren BTC is on eth pegged to btc so you can lend it and interact with other dapps
Examples of crypto bridges:
- xPollinate
- backed by two companies NOT affiliated with companies you can bridge to, mainly created to collect fees
- Matic bridge (now polygon brdige)
- developed by polygon team to help people get on the true polygon network rather than hold matic token on eth network
- Binance bridge
- by binance company to help move people to move to the binance bsc chain
Issues with bridges, that it is still up to the user to do their own research and check reviews when choosing the bridge.
uses:
- to move funds from one blockchain to the other
- enable cross-chain communication
How to use polygon bridge: wallet.polygon.technology/bridge
(polygon wrapped eth)>> the idea of the token
- withdraw ether (PoS - WETH)
- put the amount
- use PoS bridge NOT Plasma bridge, otherwise it will take about 7 days
- click transfer (takes 45 ins-3 hrs), cannot be canceled, and you pay gas in this case wrapped eth
- continue
- Fast withdraw charge lower gas fees
- but polygon bridge is safer
How does gnosis safe work?
- Gnosis Chain is an EVM-based Ethereum sidechain (L2 chain)
- Token used to transact on gnosis is xDAI, a stable token
- cheapest transactions sub cent transaction
- decentralized, secure and cost effective
- largest defi project on gnosis chain by tvl is curve finance (3 pool wrapped dai, usdc and usdt)
- stakewise >> liquid staking to gnosis chain
- other projects
- Gnosis Safe is a smart contract wallet running on Ethereum that requires a minimum number of people to approve a transaction before it can occur (M-of-N)
- Gnosis Safes are commonly used to manage pooled DAO funds. DAOs often require a certain number of members to sign off on any fund transfers. DAO actions are generally voted upon by all members and then executed by the core group of signers.
- Zodiac: exit, bridge, delay and reality:
- Bridge: This module enables a DAO on one chain to control assets and interact with systems like a Gnosis Safe on a different chain.
- Smart contract:
- M-of-N transactions: represents the number of parts, and the M represents the minimum number of those parts you need to make this process work
- You take something that has significant value — in this case, the private key in a public-private key pair, and you make it necessary for a group of people to be involved in using it, rather than just one.
- According to Thales (who sell hardware security modules), M of N is also called ‘multi-person control’ or ‘quorum-based authentication’. So the two key elements inherent in the names here are more than one (person, as in a key-holder) and ‘quorum’.
- they did performed formal verification of the contracts, time intensive
- components
- gnosis ui
- gnosis safe smart contracts
- safe transaction service: API to store off-chain signatures
- safe apps: enable extra functionality such as governance, fair auctions
- each safe has its own proxy
- https://www.youtube.com/watch?v=_2ZJ5HBEfUk&ab_channel=dearesthui
How does Metamask work?
- DeFi wallet
- its restriction to only work with token written ERC-20 protocol
- MetaMask distinguishes itself from other wallets with its user friendliness and simplicity.
- As a decentralized wallet, MetaMask has no central authority to which you can appeal for help. It is a non-custodial wallet: you own your funds as long as you have access to them with your Secret Recovery Phrase.
- MetaMask works by securely connecting to a decentralized application using a JavaScript plugin like Ethers or Web3js to define the interaction between Smart Contracts and MeteMask.
- For example, the Metamask wallet is so versatile that they support over 450,000 coins on the Ethereum blockchain.
- Also, MetaMask supports multiple blockchains such as POlygone, BNB Chain, Avalanche, and so on.
- binance smart chain bns
- polygon
- avalanche
- Avalanche is a blockchain platform capable of general purpose smart contract execution. It is a base layer, or layer 1 (L1) , which can connect to sidechains and support layer 2 (L2) solutions. Avalanche calls sidechains and L2s subnets.
- cronos:
- Cronos is a Layer 1 EVM Blockchain based on the Cosmos SDK. The closest competitors to Cronos are BNB and Polygon.
- harmony:
- Harmony (ONE) blockchain is an L2 blockchain platform built on the Ethereum network, making it easier for developers to create decentralized apps (DApps).
- fantom:
- Fantom, like Ethereum, is a Layer 1 (L1) chain , allowing decentralized apps (dApps) to be built on the network. Throughout 2021, Fantom's ecosystem has helped it become a top L1 chain, as it offers a fast, reliable, and cheap (in terms of transaction fees) alternative to Ethereum.
- eos:
- L1
- celo
- Celo is a layer 1 protocol and blockchain platform, and the Celo Mainnet is entirely separate from the Ethereum network. evm compatible (EVM-compatibility means creating an EVM-like code execution environment that makes it easy for Ethereum developers to migrate smart contracts to an EVM compatible chain without having to write the code from scratch again.)
- wallet is a digital medium that stores sets of private and public keys which allow you to access a certain location in the blockchain where your assets are
- the wallet doesn’t store assets
- all assets are on the blockchain the wallet stores keys to track ownership
- more key ring than wallet
- gateway to communicate with the blockchain than an actual wallet
- software wallet, hot wallet, communicates with ethereum blockchain not with btc
- browser extension or phone app
- deterministic wallet : one direction flow, you can derive everything from the seed phrase but not the other way around
- account addr, public and private keys
- asymmetric cryptography:
- symmetric: lock and key, you can pass on the key
- asymmetric: one lock, several math-connected keys (one open, open-close)
- the public key is like a mailbox, but the private key is the key you hold to open the mailbox
- public key encrypts the data, while the corresponding private key decrypts the data
- private keys are also used to sign transactions. private key creates a unique signature by mixing the transaction message with the private key, which proves you own the asset you want to transfer without revealing your private key, then the receiver uses the public key to verify the signature
- allows different transactions:
- swap
- send/receive
- interact with dapp
- mint nft
- MetaMask only supports Ethereum-based tokens, which excludes the world's biggest cryptocurrency – Bitcoin.
- cannot hold bitcoin because it is ethereum-based
- one of the disadvantages include only working with ERC-20 tokens, and requiring wrapping which not a lot of people are comfortable with
- why so popular:
- Because of its simplicity, availability across devices, integration with exchange and NFT websites, and support for thousands of tokens across multiple blockchains, it's easy to see why MetaMask is a popular wallet.
- competitors:
- coinbase v metamask:
- MetaMask, for instance, has moved from a simple plug-and-play add-on wallet on your browser and now operates as one of the most successful applications on the Ethereum ecosystem, bringing the dream of Web 3.0 closer to reality.
- Coinbase Wallet, on the other hand, has also made significant gains by going after a mainstream user base that is more focused on privacy and safety. These two wallets have become milestones in the world of decentralized finance.
- This software wallet recently integrated a feature that lets you swap tokens on the app as opposed to first connecting to a decentralized exchange such as Uniswap. The feature scours through the DeFi landscape to offer the trader the best liquidity deal and at the lowest fees. This means anyone can now exchange tokens from their MetaMask wallet.
- MetaMask offers integration with hardware wallets such as Ledger Nano for boosted secure storage of your funds.
| ㅤ | meta | coinbase |
| pros | Open-source and non-custodial Easy to use and supports all tokens on Ethereum Available on popular browsers | Self-custodial wallet Developed by world-leading Coinbase exchange team Mobile app available on Apple and Android Backed by Coinbase support team |
| cons | It is a hot wallet Only supports Ethereum’s blockchain | As a hot wallet, it is not the most secure Arguably one of the more centralized standalone wallets |
MetaMask Better for dApps, Coinbase for More Assets
Also, despite Coinbase Wallet’s integration with multiple blockchains, it still cannot level up to MetaMask’s capacity to connect with every dApp on the Ethereum ecosystem, which is the biggest DeFi ecosystem at the moment.
Decentralized versus centralized wallet:
Hop Protocol
- also supports rollups like arbitrum and optimism
Rollups:
- Zero-knowledge rollups (ZK-rollups) are layer 2 scaling solutions that increase throughput on Ethereum Mainnet by moving computation and state-storage off-chain. ZK-rollups can process thousands of transactions in a batch and then only post some minimal summary data to Mainnet.
- optimistic rollups
Arbitrum: can be added to metamask
- Arbitrum is a type of technology known as an optimistic rollup. It allows Ethereum smart contracts to scale by passing messages between smart contracts on the Ethereum main chain and those on the Arbitrum second layer chain.
- Arbitrum One is a layer 2 solution created by Offchain Labs. The team solves Ethereum scalability with multi-round interactive Optimistic Rollup (i.e. one of the mainstream layer 2 solutions). In addition to Arbitrum One, Offchain Labs also launched Arbitrum Nova, a new Layer 2 network based on AnyTrust technology.
Optimism:
- Optimism is a fast, stable, and scalable L2 blockchain built by Ethereum developers, for Ethereum developers. Built as a minimal extension to existing Ethereum software, Optimism's EVM-equivalent architecture scales your Ethereum apps without surprises.
difference:
- Arbitrum and Optimism are Ethereum Layer 2 (L2) solutions boosting the scalability of the blockchain – and investors are taking notice.
- Optimism and Arbitrum are both EVM compatible, Optimism uses Ethereum's EVM, whereas Arbitrum runs its own Arbitrum Virtual Machine (AVM). This results in Optimism having only a Solidity compiler, while Arbitrum supports all EVM compiled languages (Vyper, Yul, etc).
l2 metamask news 2021
Our new Custom Networks API is our latest step on the way to seamless cross-chain user experiences in MetaMask. It allows developers to recommend a variety of chains to their users, including Layer 2 networks.
Layer 2 networks is the best immediate solution to Ethereum’s high gas fees,
Our new Custom Networks API is our latest step on the way to seamless cross-chain user experiences in MetaMask.
currently available l2s:
- polygon
- arbitrum
- optimism
side chains:
- skale
- xdai
any evm compatible chain, including enterprise
l2 versus sidechain:
both to scale
The main difference between sidechains and Ethereum layer 2 solutions is that while layer 2 inherits the security of the main Ethereum network, sidechains rely on their own security.
An Ethereum sidechain is a separate blockchain network that runs in parallel to the Ethereum main chain. Sidechains connect to the main chain via a two-way peg system allowing assets to be exchanged between the chains.
There are two basic types of sidechains, one in which a chain is dependent on the other and another where they are independent.
When one chain is dependent on another chain like Ethereum, it can be considered the child chain of this parent chain. Typically, the child chain doesn’t create its own assets and derives any assets from transfers from the parent chain.
Sidechains have their own consensus protocols that are often designed for specific kinds of transactions and allow them to be faster and more affordable.
Sidechains reduce the congestion on the main chain, reducing the cost for everyone and increasing the usability and scalability of the Ethereum ecosystem.
Polygon PoS, Skale, and Rootstock
Layer 2 protocols are chains that live inside the Ethereum chain but are able to achieve greater scalability through a secondary framework.
This reduces congestion on the main layer by having the bulk of activity processed through the second layer. Unlike a sidechain, layer 2 generally inherits the security properties of the main chain.
Simply put, layer 2 compresses bundles of transactions and submits them to the main Ethereum network.
Layer 2 scaling solutions include channels, rollups, and plasma.
Here’s a breakdown of each of these individual solutions:
Product analyst
Individual interviews, feedback surveys
usability tests
benefits:
- validate prototype
- better ux
- adds context to other data (heat maps might show where users are on the site, usability tests tell you why?
- empathize with customers
- instead of endless iterations
- helps get buy-in for change
how?
- watch how people use the product remotely (hotjar session recordings, but I just did it live), where people struggle and what drives them to convert
- beta testing - test run prerelease, done by real users in a real environment not staging
- Alpha Testing is done within the organization, while Beta Testing is done in the user's environment. During Alpha Testing only functionality and usability are tested, while during Beta Testing usability, functionality, security, and reliability are tested to the same depth.
- Alpha testing is the first end-to-end testing of a product to ensure it meets the business requirements and functions correctly. It is typically performed by internal employees and conducted in a lab/stage environment
- type of acceptance test
