HIP-1292: Hiero AnonCreds Method

Author	Keith Kowal (keith.kowal@hashgraph.com)
Working Group	Diane Mueller (diane@hbar.fund), AlexanderShenshin
Discussions-To	https://github.com/hiero-ledger/hiero-improvement-proposals/pull/1292
Status	Active ⓘ
Needs Hiero Approval	No ⓘ
Type	Informational ⓘ
Created	2025-08-25
Updated	2025-10-22

Abstract
Motivation
Rationale
Specification
Request
Security Considerations
References
License

Abstract

This Information HIP introduces the Hiero AnonCreds Method, a specification for publishing and resolving AnonCreds objects—such as schemas, credential definitions, and revocation registries—on Hiero networks. Once established, the method will be submitted to the Hyperledger AnonCreds Methods Registry to enable ecosystem visibility and alignment.

Motivation

AnonCreds is the leading privacy-preserving credential format with broad adoption across self-sovereign identity (SSI) ecosystems. To integrate Hiero networks into this landscape, we must publish a clear method specification describing how AnonCreds objects are stored and resolved via Hiero networks.

By publishing the method, we enable everyone to build compatible libraries and agents, and we align Hiero networks with existing AnonCreds VDRs like Indy, Cheqd, and Cardano.

Rationale

Interoperability: Having a published method ensures interoperability across agents, wallets, and identity ecosystems.
Inclusivity: Anyone can implement against the method—whether using the Hiero Python DID repo, Hiero JS DID repo, ACA-Py plugins, or custom tools.
Discoverability: Listing in the Hyperledger AnonCreds Methods Registry shows the community that Hiero networks supports AnonCreds.
Governance: A Hiero repo provides versioning, updates, and clarity for maintainers and contributors.

Specification

High-Level Summary

The Hiero AnonCreds Method defines how AnonCreds objects are anchored, resolved, and maintained on the Hiero network:

Schemas: JSON schema definitions are stored using Hiero Consensus Service (HCS), aligned with HCS-1 file storage conventions.
Credential Definitions: Published as HCS objects containing cryptographic material for credential issuance and verification.
Revocation Registry Definitions: Anchored on HCS for long-term persistence.
Revocation Registry Entries: Updated dynamically on-chain, providing real-time revocation status.
Resolution: Performed through Hiero Mirror Node APIs, allowing verifiers and wallets to retrieve the latest state.
Identifiers: Objects are referenced using DID-compatible identifiers (<issuer-did-on-hedera>/anoncreds/<anoncreds-version>/<object-type>/<hcs-topic-id>).

Alignment with DID Methods

The method extends the Hedera DID approach (HIP-762) by providing specific rules for AnonCreds object handling.

Similar to how DID methods are published to help developers understand the lifecycle of DIDs, the AnonCreds Method must be published to help developers understand how credential data is created, updated, and resolved on Hiero networks.

Example Resources

Draft spec: DSR Hedera AnonCreds Method
Hyperledger Registry: AnonCreds Methods Registry
DID context: W3C DID Extensions – DID Methods

Reference Implementations

Existing Hiero ecosystem libraries already support AnonCreds operations and serve as proof points:

[Hiero Python DID repo] – Python SDK support for DID resolution and credential flows
[Hiero JS DID repo] – JavaScript SDK support for DID resolution and AnonCreds integration

These demonstrate how to implement the method and will benefit from a formal, discoverable specification.

Submission to Hyperledger Registry

Hiero will submit the AnonCreds Method to the Hyperledger AnonCreds Methods Registry by creating a PR with:

A new Markdown file describing the method (method-anoncreds-hedera.md)
Metadata in specs.json including method identifier, maintainers, and spec link
Reference to the hiero-anoncreds-method GitHub repo

This ensures Hiero networks such as Hedera appears alongside other recognized AnonCreds VDRs like Indy, Cheqd, and Cardano.

Request

This HIP proposes:

Host Hiero Anonreds Method in appropriate Hiero repo.
Submission of the method entry into the Hyperledger AnonCreds Methods Registry.
Ongoing updates and community contributions through Hiero governance.

Security Considerations

The method spec itself introduces no new risks, but ensures secure anchoring and resolution flows are well-documented, reducing the chance of insecure ad-hoc implementations.