G-Series: FX Pegging Model & Price Feeds
G-Series Stablecoin 2.0 is an FX-pegged stablecoin family
To maintain a robust link between each G-Series token and its target fiat currency, the protocol relies on:
an FX-aware collateral model
a multi-source price feed architecture for both USD and local FX rates
This section explains how the peg is maintained and how price/FX data is sourced, aggregated, and used inside the protocol.
1. FX Pegging Overview
Each G-Series stablecoin (e.g., GKRW, GJPY, GTHB, GVND) is soft-pegged to its reference fiat currency through:
USD-based collateral at the GUSD layer
FX-linked parameters (collateral ratios, haircuts, safety margins, liquidity indicators) at the G-Series layer
Conceptually:
G-Series tokens represent claims denominated in local currency units
but are ultimately backed by USD stablecoins and RWAs at the GUSD layer
The protocol does not promise an absolutely rigid peg at all times. Instead, it is designed to:
maintain a tight operational band around the target FX value
remain solvent and liquid across a wide range of market conditions
2. Oracle and Price Feed Architecture
The protocol does not rely on a single oracle. Instead, it combines three broad categories of data:
On-chain DEX Data
Centralized Exchange (CEX) Data
Institutional FX / Off-chain Feeds
These sources are aggregated to produce a clean internal FX/price feed used by G-Series.
1) On-chain DEX Data
On-chain data is the most transparent and directly verifiable source of prices for:
pairs such as GUSD/USDT, GUSD/USDC,
and G-Series pairs such as GKRW/GUSD, GJPY/GUSD, where liquidity is available.
Key design points:
Use of TWAP (Time-Weighted Average Price) over a defined window to reduce the impact of:
short-term volatility
price manipulation attempts (e.g., flash loan attacks)
Preference for deepest, most liquid pools across supported chains and DEXes.
Continuous monitoring for:
abnormal slippage
suspicious volume spikes
on-chain anomalies
2) Centralized Exchange (CEX) Data
CEX markets are used as a reference for:
major crypto pairs (e.g., BTC/USDT, ETH/USDT)
major stablecoin pairs (e.g., USDT/USDC)
in the future, potential GUSD or G-Series listings
Key design points:
Use of ticker and order book mid-prices from multiple exchanges.
Elimination of outlier quotes and venues that show abnormal spreads or illiquidity.
Optional use of volume-weighted averages across exchanges.
3) Institutional FX / Off-chain Feeds
For fiat FX rates (e.g., USD/KRW, USD/JPY, USD/THB, USD/VND), the protocol references:
institutional-grade FX data providers
bank or financial market APIs
other high-quality macro FX feeds
Key design points:
Only sources with sufficient track record and reliability are used.
Multiple feeds are combined to avoid over-reliance on any single vendor.
Stale or inconsistent feeds are discarded or down-weighted.
3. Aggregation Pipeline
The three data categories are processed through an aggregation pipeline to produce the final internal feed:
On-chain DEX TWAP CEX Tickers / Order Books Institutional FX Feeds → Aggregator → Clean FX / Price Feed
1) Normalization
Raw inputs are normalized to a consistent format:
all prices expressed in standard base/quote pairs (e.g., USD/KRW, GUSD/USDT)
timestamps, volumes, and confidence indicators aligned
data quality flags attached (freshness, spread, liquidity)
2) Filtering and Outlier Rejection
The aggregator applies filters to remove or down-weight:
stale data beyond a defined maximum age
quotes with abnormally wide spreads
venues with suspicious volume or behavior
extreme outliers outside a reasonable deviation band from the median
3) Weighted Aggregation
After filtering:
prices are combined using weighted medians or volume-weighted averages,
with configurable weights per source type:
on-chain DEX data may be favored where liquidity is strong
institutional FX feeds may be prioritized for fiat currency pairs
CEX data can provide redundancy and cross-checks
The final output is a Clean FX/Price Feed used internally by the protocol.
4. Use of Price Feeds in the G-Series Model
The clean feed is used in several key areas:
1) Minting and Burning
Convert between:
GUSD and G-Series amounts
different G-Series assets (via GUSD)
Determine how many units of G-Series to mint or burn for a given amount of GUSD.
Ensure that, after each operation:
collateral ratios remain above target ranges
FX-linked liquidity metrics (FX-LCR) stay within safe bounds
2) Risk Metrics and Guardrails
Price feeds drive:
recalculation of:
Collateral Ratio (CR) for G-Series
FX-LCR and related liquidity indicators
mark-to-market values of reserves and liabilities
application of haircuts on:
specific assets (e.g., certain stablecoins or RWAs)
specific FX pairs under stress
triggering of safety responses:
tightening minting limits
increasing haircuts or safety margins
or, in extreme cases, temporarily pausing certain operations
3) Internal Accounting and Reporting
Internal balance sheet views
monitoring dashboards for volatility and FX exposure
and periodic reporting (where applicable) to stakeholders and regulators
5. Safeguards, Fail-Safes, and Degraded Modes
Because price and FX data are critical to peg stability, the protocol includes safeguards for:
Stale or Missing Data
Source Divergence and Anomalies
Emergency and Governance Intervention
1) Stale or Missing Data
If a critical portion of feeds becomes stale or unavailable:
confidence scores for those feeds are reduced to zero
the system may:
widen safety margins (σ),
increase haircuts, or
limit minting and complex operations.
In extreme cases, the protocol can:
switch to degraded mode, allowing only:
redemptions
or controlled operations, until reliable data is restored
2) Source Divergence and Anomalies
If major sources disagree beyond a predefined threshold:
the aggregator may:
ignore extreme outliers
down-weight problematic venues
or temporarily rely more heavily on on-chain data or institutional FX feeds, depending on context
Parameters such as σ, haircuts, and allowed slippage are automatically adjusted to defend the peg and buffers.
3) Governance and Emergency Controls
In early phases:
a foundation, multi-signature committee, or designated risk entity may have limited powers to:
override or update oracle configuration
introduce new sources or disable compromised ones
trigger circuit breakers in case of obvious manipulation or system-wide crises
Over time:
these controls are expected to be formalized under governance
with clear on-chain rules and transparent procedures for:
adding/removing oracle sources
adjusting weights and thresholds
and handling extraordinary events
6. Summary
The G-Series FX peg is not based on a single feed or simple 1:1 promise, but on:
multi-layer collateralization via GUSD
a multi-source price/oracle architecture that combines on-chain DEX data, CEX markets, and institutional FX feeds
By:
aggregating and filtering data
applying risk-aware parameters (CR, FX-LCR, σ, haircuts)
embedding fail-safes and governance controls
the protocol aims to keep G-Series:
closely aligned with their target fiat currencies
resilient against market volatility, data issues, and localized failures
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