papers/lux-oracle-infrastructure/sections/02-traditional-price-oracles.tex

\section{Traditional Price Oracles}


\subsection{Chainlink Integration}

Lux integrates Chainlink's decentralized oracle network to leverage its extensive infrastructure of node operators and data providers. The integration follows Chainlink's aggregator pattern:

\begin{lstlisting}[caption={Chainlink Price Feed Interface}]
interface IPriceFeed {
    function description() external view returns (string memory);
    function aggregator() external view returns (address);
    function latestAnswer() external view returns (int256);
    function latestRound() external view returns (uint80);
    
    function getRoundData(uint80 roundId) 
        external view returns (
            uint80 roundId,
            int256 answer,
            uint256 startedAt,
            uint256 updatedAt,
            uint80 answeredInRound
        );
}
\end{lstlisting}

\subsection{Pyth Network Integration}

Pyth Network provides high-frequency price updates with sub-second latency, crucial for derivatives trading:

\begin{itemize}
    \item \textbf{Pull-based updates}: Validators fetch prices on-demand
    \item \textbf{Confidence intervals}: Each price includes uncertainty bounds
    \item \textbf{Publisher diversity}: Aggregates from 70+ first-party publishers
    \item \textbf{Cross-chain availability}: Native support for Lux's multi-chain architecture
\end{itemize}

\subsection{Median Aggregation Algorithm}

To ensure price reliability, Lux employs a robust median aggregation mechanism:

\begin{equation}
P_{final} = \text{median}\{P_1, P_2, ..., P_n\}
\end{equation}

Where $P_i$ represents individual price feeds. The median approach provides resistance to manipulation:

\begin{equation}
\text{Manipulation Cost} = \lceil \frac{n+1}{2} \rceil \times \text{Feed Cost}
\end{equation}

\subsection{Update Frequency and Latency}

The oracle system implements adaptive update frequencies based on market conditions:

\begin{lstlisting}[caption={Fast Price Feed Implementation}]
contract FastPriceFeed is ISecondaryPriceFeed {
    uint256 public constant MAX_PRICE_DURATION = 30 minutes;
    uint256 public priceDuration;
    uint256 public maxPriceUpdateDelay;
    
    struct PriceDataItem {
        uint160 refPrice;      // Chainlink price
        uint32 refTime;        // Last updated timestamp
        uint32 cumulativeRefDelta;   // Cumulative price delta
        uint32 cumulativeFastDelta;  // Fast price delta
    }
    
    function setPrice(address token, uint256 price) 
        external onlyUpdater {
        require(block.timestamp < lastUpdatedAt + maxPriceUpdateDelay);
        
        PriceDataItem memory data = priceData[token];
        uint256 refPrice = getRefPrice(token);
        uint256 deviation = getDeviation(price, refPrice);
        
        require(deviation < maxDeviationBasisPoints);
        prices[token] = price;
        lastUpdatedAt = block.timestamp;
    }
}
\end{lstlisting}