DIP-1 Fundamental Infrastructure Proof Systems (FIPS)
Abstract
This proposal aims to standardize and enhance the structure and processes of Fundamental Infrastructure Proof Systems (FIPS) to ensure more efficient and secure verification of infrastructure attributes within the Witness Chain’s DePIN Coordination Layer (DCL).
Motivation
Current FIPS implementations, such as Proof of Diligence, Proof of Location, and Proof of Bandwidth, establish a foundation for building physical trust in digital systems. However, the scope of physical assets and their attributes is vast, presenting an opportunity to expand and standardize the approach to unify physical trust. This proposal aims to set comprehensive standards for building and maintaining physical trust across various asset types. By doing so, it will streamline the design and implementation of new proof systems, facilitating consistency, reliability, and their integration to DCL.
Specification
FIPS refers to any proof system that translates a specific infrastructure attribute into digital proofs that can be verified, processed, and acted upon within a blockchain framework, such as location, bandwidth, energy capacity and more. There are two primary roles in FIPS:
- Prover: an infrastructure node that owns, controls or enables the specific attribute needing verification.
- Challenger: registered participants with the ability to actively or passively measure and validate the claimed states of the prover.
Generally, FIPS accepts request to verify a claimed attribute (denoted as X) associated with the Prover. Each request triggers a challenge, where challengers interact with the prover to verify X. The output of a challenge includes the measurement of X as well as a proof-of-X (PoX).
Each FIPS needs to specify a set of procedures for provers and challengers to execute the verification process. The system comprises both on-chain and off-chain modules to implement its functionality.
The on-chain modules of FIPS contain three main components:
- FIPS Registry: a smart contract managing participant registration and keeping records of their public properties and status.
- Registry Manager: a profile smart contract that defines the selection and reward schemes for executing a challenge. It is instantiated by specifying the registry it functions on.
- Challenge Coordinator: a smart contract implementing the challenge coordination logic and verification process.
The off-chain modules are specialized for different participant roles and consist of two parts for each role:
- Registry: a database managing the private properties and status of participants.
- Prover / challenger process: off-chain programs used to collect data necessary for state verification.
FIPS Example
Proof of Bandwidth functions similarly to a decentralized speed test, evaluating the internet connectivity capabilities of network hotspots (provers). In this system, challengers are internet servers tasked with generating and sending small data packets to prover nodes. The backhaul bandwidth is measured based on the response rate, as specified in the challenger process. Once the prover receives a sufficient number of packets, it responds to the challengers and reports the data receipt to the challenge coordinator, following the prover process. The challenge coordinator collects and aggregates the challengers’ measurements, resulting in a verifiable proof of bandwidth.
Reference Implementation
[1] Proof of Diligence: Watchtower securing rollup states
Security Considerations
To ensure the reliability of FIPS, it is crucial to specify trust models for provers and challengers, addressing scenarios such as trusted settings, rational adversaries, and Byzantine faults. Under these different models, the system design must consider and mitigate various security threats, including but not limited to:
- Data Integrity: Ensuring that all data collected and processed within FIPS is tamper-proof through the use of cryptographic primitives or secure storage solutions.
- Participant Authentication: Implementing access control to prevent unauthorized access, ensuring that only registered participants can engage in the challenge process.
- Proof Validation: Enhancing the challenge process to detect and prevent fraudulent claims, thereby ensuring that only legitimate proofs are accepted.
- Slashing Trails: Maintaining comprehensive logs of all interactions and transactions within FIPS to enable thorough audits and traceability. This supports slashing mechanisms to enforce economic security by penalizing dishonest behavior.