Chainlink Ecosystem Overview

Transcript

1. Yo-an Lin (c9s) 2021
   Chainlink Overview
   The ecosystem, how does it work?
   And the real side
   

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2. ChainLink
   History
   • Chainlink was created in 2014, though it didn’t launch until 2017. Its founder
   is Sergey Nazarov, a 32-year-old entrepreneur who has a major presence in
   the crypto market.
   
   • Originally, the Chainlink network was designed to be a centralized oracle
   system that can verify incoming information. However, it has since morphed
   into what it is today: a decentralized oracle network that pairs with smart
   contracts to provide secure transactions using external data sources and
   APIs.
   

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3. ChainLink
   Price History
   • When Chainlink’s LINK tokens
   fi
   rst hit the market in 2017, they traded for just
   above a cent in USD. The cryptocurrency’s market capitalization was also
   understandably quite low.
   
   • Prices stayed this way for a while, trading at less than a dollar per token until
   mid-2019, when the price per token increased, and it began trading at
   between $1 and $4 per token. However, for the latter half of 2020, LINK
   tokens began to increase in price even more to over $14. In February 2021,
   LINK reached an all-time high price of nearly $37 per token.
   

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5. The Ecosystem
   Roles
   • Data Clients (mainly DeFi applications)
   
   • Smart Contract Developers
   
   • ChainLink Node Operator (CL Node)
   

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6. The LINK token
   

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7. The LINK token
   • ERC-677 (proposed by ChainLink developers)
   
   • The ERC-677 issue is not closed yet. Hence it’s not a approved standard.
   
   • ERC-20 compatible token
   
   • transferAndCall method (let you transfer a token and call a method on
   contract)
   

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11. Chainlink Node
    

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12. Chainlink Node
    Requirement
    • An oracle contract (one-to-one relationship to the node)
    
    • PostgreSQL (for storing jobs, runs and wallet keys)
    
    • Low hardware requirement: 2GB~4GB memory is enough.
    
    • Blockchain node endpoint (for Ethereum, you can use geth, infura.io or
    chainstack)
    
    • Wallet key for the node. (For writing transactions to the blockchain)
    
    • Gas tokens in the wallet (for Ethereum, it’s ETH)
    

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13. Oracle
    Contract
    Chainlink
    
    
    Node
    Chainlink
    
    
    Node Wallet
    Aggregator
    Contract
    Monitoring and Sign transaction
    transferAndCall
    Blockchain
    one-to-one relationship
    

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15. Chainlink Node
    Components
    • An Oracle contract
    
    • Jobs (Oracle contracts use JobID to call the API on the node)
    
    • Runs
    
    • Bridges
    
    • Core Adaptor
    
    • External Adaptor (an adaptor connecting to external web service via JSON
    api)
    

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16. The Oracle Contract
    // SPDX-License-Identifier: MIT
    
    
    pragma solidity 0.4.24;
    
    
    import "@chainlink/contracts/src/v0.4/Oracle.sol";
    

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17. Chainlink Node
    Jobs
    • Each Chainlink Node has its own unique job entry (unique job ID).
    
    • JobID is an UUID.
    
    • Oracle contracts use the JobID to execute the API de
    fi
    ned on the node.
    
    • Jobs de
    fi
    ne the task sequence.
    

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20. Chainlink Node
    Calling Jobs with core adaptor
    

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21. Chainlink Node
    Calling Jobs with core adaptor
    

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23. Chainlink Node
    External Adaptor
    • External Adaptors are just web services with the required JSON request/
    response speci
    fi
    cation.
    
    • You register the external adaptor via the Chainlink Node bridge, so that Jobs
    can get the data from the external adaptor.
    
    • An external adaptor can be a service written in any programming language.
    

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26. Price Feeds
    • Major Price Feeds are maintained by Chainlink O
    ffi
    cial. (They also pay the gas
    fee and LINK token to the oracle contracts)
    
    • Price feed contracts are not open sourced. They are hidden behind the proxy
    contract.
    
    • Some companies did the reverse engineering to implement their own price feed.
    
    • To join the major price feed oracle network, you need to join the Oracle
    olympics.
    
    • To add a new token to the o
    ffi
    cial price feed, $3M market cap is the minimal
    requirement.
    

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27. Price Feed
    Using price feed as a Chainlink Client
    

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28. The Official Price Feed Arch
    

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29. Feed Registry
    

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32. An internal document that describes the oracle olympics
    

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33. Aggregator
    • Aggregator calls the oracle network.
    
    • There are 2 kinds of aggregator:
    
    • Flux Aggregator - no o
    ffi
    cial documents, only client tutorial. Contract-
    based, high cost.
    
    • O
    ff
    -chain Reporting (OCR), no o
    ffi
    cial documents as well. O
    ff
    -chain
    computing with a consensus algorithm.
    

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34. Chainlink Market
    

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39. Wrap up
    • You receive LINK token from your oracle contract.
    
    • You burn ETH token as the gas token to send the result as a txn.
    
    • One oracle contract can only have one CL node running.
    
    • You don’t need LINK token to run a CL node.
    
    • Chainlink node are isolated, you can not join the price feed by yourself.
    
    • Price feed smart contracts are closed source. (Club member only)
    
    • No o
    ff
    -chain reporting and
    fl
    ux aggregator documentation. (Club member only)
    

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40. Comments from Community
    

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49. Q & A
    

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