Resource Token Standard

The standard provides a common API (e.g., ERC-20, ERC-721, or custom extensions) that allows DePIN networks to mint, track, and transfer tokens representing resource units. This ensures interoperability across wallets, marketplaces, and other smart contracts. Key functions typically include:

• Minting/Burning: Creating or destroying tokens as resources are provisioned or consumed.
• Balance Tracking: Querying the amount of a specific resource a user owns or has staked.
• Transferability: Enabling peer-to-peer trading of resource credits on secondary markets.

Resource tokens can follow different models based on the underlying asset's nature:

• Fungible Credits (ERC-20): Used for homogeneous, divisible resources like storage gigabytes or compute hours. One token is interchangeable with another.
• Non-Fungible Tokens (ERC-721/1155): Represent unique, non-interchangeable resources, such as a specific sensor device, a dedicated GPU node, or a parcel of geospatial data.
• Semi-Fungible Models: Hybrid approaches where tokens have both fungible (e.g., capacity) and non-fungible (e.g., location, specs) attributes.

Resource tokens are not standalone; they require verifiable data feeds to maintain integrity. Oracles bridge the physical and digital worlds by attesting to resource availability and usage. This integration enables:

• Proof-of-Physical-Work (PoPW): Tokens are minted or rewards distributed only upon cryptographic proof of real-world resource contribution (e.g., providing valid storage proofs).
• Dynamic Pricing: Token supply and value can be algorithmically adjusted based on oracle-reported network demand and capacity.
• Slashing Mechanisms: Malicious or offline resource providers can have their staked tokens penalized, enforced by smart contract logic.

Several major DePIN projects implement resource token standards:

• Filecoin (FIL): Uses its own protocol to tokenize storage capacity and storage deals, with tokens representing provable storage space and time.
• Render Network (RNDR): Tokens represent GPU compute cycles for rendering jobs, distributed to node operators who complete work.
• Helium (HNT & Data Credits): HNT is the network token, while Data Credits are a non-transferable, burned token representing wireless bandwidth usage.
• Akash Network (AKT): Uses its token to represent and lease cloud compute resources, with deployment leases settled on-chain.

Beyond pure representation, resource tokens are fundamental to DePIN economics and governance:

• Incentive Alignment: Tokens reward resource providers and coordinate supply-side participation.
• Capital Formation: Token sales can fund initial hardware deployment and network bootstrapping.
• Governance Rights: Token holders often vote on protocol upgrades, resource pricing parameters, and treasury allocations.
• Collateral & Staking: Providers must often stake tokens as collateral to guarantee service quality and deter malicious behavior, creating a skin-in-the-game mechanism.

Implementing a robust standard involves navigating several challenges:

• Abstraction Gap: Ensuring the on-chain token accurately reflects the state of an off-chain, physical resource.
• Regulatory Clarity: Determining if a resource token constitutes a security, utility, or commodity token under various jurisdictions.
• Interoperability: Moving beyond single-chain standards to cross-chain resource tokens that can be used across multiple ecosystems (e.g., via IBC or bridging).
• Custom Extensions: Many projects build atop base standards (like ERC-20) with custom logic for slashing, vesting, or resource-specific attributes.

The standard specifies a set of mandatory smart contract functions that all compliant tokens must implement. These include:

• mint(address to, uint256 amount): Creates new tokens, typically restricted to authorized resource providers.
• burn(uint256 amount): Permanently destroys tokens, often used to pay for network fees or resource consumption.
• transfer(address to, uint256 amount): Moves tokens between user accounts.
• balanceOf(address account): Queries the token balance of a given address.
• totalSupply(): Returns the total circulating supply of the resource token.

This standard abstracts underlying physical resources (like compute, storage, or bandwidth) into a uniform, tradable digital asset. It establishes a market-based pricing mechanism where the token's value is derived from the supply of the resource and the demand for its consumption. This allows for dynamic pricing models, such as burn-and-mint equilibrium, where tokens are burned to access resources and minted to reward providers.

Unlike standard fungible tokens (e.g., ERC-20), minting rights are typically restricted. A governance mechanism or a designated oracle/validator set controls who can mint new tokens, ensuring the token supply accurately reflects the availability of the real-world resource. This prevents inflation and maintains the token's peg to the underlying resource's utility.

A defining feature is the burn function as a payment method. To consume a unit of the network resource (e.g., execute a smart contract, store data), a user must burn a corresponding amount of tokens. This creates a sink for the token, directly linking its economic model to network usage and ensuring providers are compensated through the minting of new tokens.

By conforming to a known token standard, resource tokens become composable within the broader decentralized finance (DeFi) ecosystem. They can be listed on DEXs for trading, used as collateral in lending protocols, or integrated into yield-farming strategies. This liquidity layer separates the token's investment and utility functions.

A core security feature is the slot-based access control mechanism. A token's slot determines which other tokens it can interact with, enabling complex, permissioned financial logic. This prevents unauthorized merging or splitting of value between incompatible assets, a risk not present in simple ERC-20 or ERC-721 tokens. For example, a token representing a loan in Slot A cannot be merged with a token representing an insurance policy in Slot B, isolating risk.

The standard's dual-ID system (token ID + slot) creates nuanced approval scenarios. Traditional approve functions are insufficient. Developers must correctly implement the setApprovalForAll and value-specific approval functions to avoid security gaps. A critical consideration is that approving a spender for a slot grants control over all tokens in that slot, which can lead to unintended asset exposure if not carefully managed.

The transferFrom and transferValue functions, which can move partial value between tokens, introduce new reentrancy attack surfaces. A malicious contract receiving value in a callback could re-enter the calling function before state updates are finalized. Standard checks-effects-interactions patterns must be strictly enforced, and consideration should be given to using reentrancy guards, especially in contracts that perform external calls during transfers.

Integrating ERC-3525 tokens into existing DeFi protocols built for ERC-20 or ERC-721 requires careful adaptation. Wrapper contracts or adapters that convert resource tokens introduce trust assumptions and additional gas costs. Incorrectly assuming fungibility (like ERC-20) or treating each ID as unique (like ERC-721) can lead to logical errors, failed transactions, or loss of the token's semi-fungible properties.

Smart contract audits for ERC-3525 implementations should prioritize:

• Slot isolation: Ensuring cross-slot operations are impossible.
• Value accounting: Verifying that _beforeValueTransfer and _afterValueTransfer hooks correctly update balances without overflow/underflow.
• Approval scoping: Confirming that approvals are granted at the intended granularity (per token, per slot, or global).
• Hook security: Auditing any custom logic in the transfer hooks for vulnerabilities.

Sui's core data architecture where all on-chain data is represented as objects. Each object has a globally unique ID, owner, and a set of key-value pairs defining its state. This differs from account-based models (like Ethereum) and enables parallel transaction execution.

• Key Properties: id, owner, version, digest.
• Types: Can be owned by an address, shared, or immutable.
• Implication: Transactions specify which objects they interact with, allowing validators to process non-conflicting transactions simultaneously.

The safe, resource-oriented programming language used to define Resource Tokens and smart contracts on Sui and Aptos. Its key feature is resource semantics, which ensures digital assets behave like physical objects: they cannot be copied or unintentionally destroyed.

• Key Concepts: struct definitions with the key and store abilities.
• Safety: Built-in protection against reentrancy and overflow bugs.
• Native to RTS: Move's type system is the foundation for creating secure, composable resource tokens.

A standardized implementation of fungible assets on Sui, built using the Resource Token Standard principles. The Coin<T> module provides a generic blueprint for creating tokens like stablecoins or governance tokens.

• Standard Interface: Functions like transfer, balance, and mint.
• Type Parameter T: The distinguishing tag (e.g., Coin<USDC>) that makes each currency unique.
• TreasuryCap: A special administrator object required to mint and burn tokens of type T, controlling supply.

A flexible, on-chain rules engine for Non-Fungible Tokens (NFTs) that governs how they can be transferred or sold. It's a core mechanism for enforcing royalties and other creator rules post-mint.

• Dynamic Rules: Can enforce a royalty percentage on secondary sales.
• Composability: Policies can be added to NFTs after creation.
• Marketplace Compliance: Buy/set transactions must resolve the relevant policy, ensuring rule enforcement across all marketplaces on the network.

A secure, standardized smart contract for listing, selling, and managing NFTs on Sui. It provides a safe environment for NFT trades that automatically respects Transfer Policies.

• Creator Protection: Guarantees royalty payments if a policy is set.
• Owner Control: The NFT owner retains custody in their personal Kiosk.
• Interoperability: Any marketplace can interface with the public Kiosk standard, reducing fragmentation.

The dominant token standards on Ethereum, providing a contrast to Sui's Resource Token Standard.

• Account-Based: Balances are stored in a central contract's internal ledger, not as discrete objects.
• Approval Model: Requires explicit approve & transferFrom calls for third-party spending (e.g., DEXs).
• Comparison: RTS objects have intrinsic ownership and can be transferred directly, eliminating the need for the approval pattern and enabling parallel processing.