Hyperledger Indy provides tools, libraries, and reusable components for providing digital identities rooted on blockchains or other distributed ledgers so that they are interoperable across administrative domains, applications, and any other silo. Indy is interoperable with other blockchains or can be used standalone powering the decentralization of identity.
{% include figure image_path="/images/private-public-permissioned-permissionless.webp" alt="this is a placeholder image" caption="@Delpadschnick | [CryptoDesign.io](https://CryptoDesign.io)" %}
> Hyperledger Indy provides tools, libraries, and reusable components for providing digital identities rooted on blockchains or other distributed ledgers so that they are interoperable across administrative domains, applications, and any other silo.
> This codebase embodies all the functionality to run nodes (validators and/or observers) that provide a self-sovereign identity ecosystem on top of a distributed ledger. It is the core project for Indy; over time, all other indy-* projects may collapse into this one, except for indy-sdk.
> This is the official SDK for Hyperledger Indy, which provides a distributed-ledger-based foundation for self-sovereign identity. Indy provides a software ecosystem for private, secure, and powerful identity, and the Indy SDK enables clients for it. The major artifact of the SDK is a C-callable library; there are also convenience wrappers for various programming languages and Indy CLI tool.
* [Blockchain for Business](https://www.edx.org/professional-certificate/linuxfoundationx-blockchain-for-business) Linux Foundation, may be freely audited and has a section about Indy.
> 2–4 hours per week, for 10 weeks. A primer to blockchain, distributed ledgers and Hyperledger technologies.
* [An overview of Self-Sovereign Identity: the use case at the core of Hyperledger Indy](https://www.hyperledger.org/blog/2019/05/01/an-overview-of-self-sovereign-identity-the-use-case-at-the-core-of-hyperledger-indy)
> Credential issuers, holders, and verifiers are peers on an SSI network. Any person or organization can play any or all of the roles, creating a decentralized system for the exchange of trustworthy, digital credentials.
>
> - Credential issuers determine what credentials to issue, what the credential means, and how they’ll validate the information they put in the credential.
> - Credential holders determine what credentials they need and which they’ll employ in workflows to prove things about themselves.
> - Credential verifiers determine what credentials to accept, and which issuers to trust.
* [Strengthening Hyperledger Indy and Self-Sovereign Identity](https://www.hyperledger.org/blog/2019/07/18/strengthening-hyperledger-indy-and-self-sovereign-identity)
> Forrester’s recent “[Top Recommendations for Your Security Program, 2019](https://www.forrester.com/report/Top+Recommendations+For+Your+Security+Program+2019/-/E-RES151535),” testifies to this, describing SSI as a “win” for customers and businesses, and urged chief information security officers (CISO) to “Empower your customers to control their own identities via self-sovereign identity.”
>
> They can do this because exchanging verifiable digital credentials is at the heart of SSI. This ends the need for massive data silos, honeypots, and unsecured data repositories housed at countless corporations and organizations. Instead, anyone can hold secure and verifiable information about themselves
* [Hyperledger Indy Explainer Video](https://www.youtube.com/watch?v=MnO2L6WoqD0) Hyperledger Foundation
> Individuals will not have to rely on big organizations to store and share their personal data. Instead the user controls what data they want to provide access to and for how long.
> Lighting talk with Nathan George (Sovrin CTO) taking the audience through a high-level look at the Sovrin DLT, how it can be public/permissioned yet still decentralized, and why this is right for identity solutions.
* [Hyperledger Identity Working Group-paper](https://docs.google.com/document/d/1ExFNRx-yYoS8FnDIUX1_0UBMha9TvQkfts2kVnDc4KE/edit#heading=h.7noli5fp1i70)
* [HyperledgerIndyWGCall_2018-12-06](https://drive.google.com/file/d/1166XpTM8WgZVMN2ca53CRCJapZlAeUhM/view) Discussion of VON and Plenum Docs (w info-graphics)
> "Byzantine fault tolerance is a sub-field of fault tolerance research inspired by the Byzantine Generals' Problem, which is a generalized version of the Two Generals' Problem."
* [Storage components](https://github.com/hyperledger/indy-plenum/blob/master/docs/storage.md) - As of now, RocksDB is used as a key-value database for all Storages.
* [indy-sdk](https://github.com/hyperledger/indy-sdk) - Everything needed to build applications that interact with an Indy distributed identity ledger.
> This repo holds RFCs for the Indy project. We call them HIPEs (Hyperledger Indy Project Enhancements, pronounced like "hype" for short). They describe important topics (not minor details) that we want to standardize across the Indy ecosystem.
* [indy-crypto](https://github.com/hyperledger/indy-crypto) - shared crypto library for Hyperledger Indy components. To be:
* [hyperledger/ursa](https://github.com/hyperledger/ursa) [[**ϟ**](https://www.hyperledger.org/blog/2018/12/04/welcome-hyperledger-ursa)][[**ϟ**](https://www.coindesk.com/hyperledger-launches-cryptography-toolbox-for-blockchain-developers)] "includes the Hyperledger Indy-Crypto code base that is the building block for anonymous credentials, the verifiable credentials protocol, in indy-sdk used by the Sovrin Network. [...] We are hopeful the shared library will help other platforms better incorporate and use ZKP-based credentials and leverage Sovrin for their identity component." (From Nathan George on Sovrin Telegram) [[**wiki**](https://wiki.hyperledger.org/display/ursa)]
### Implementation
* [IXO World](https://ixo.world/) - Guided by the UN framework of 17 Global Goals to end poverty, protect the planet and ensure prosperity for all, by the year 2030. [[**ϟ**](https://twitter.com/phillipgibb/status/1073247433067556865)] (ethereum ocean ipld)
>"Achieving the Sustainable Development Goals demands embracing the data revolution " UN Secretary - General (2014)
* [Legal Entity Identifier blockchained by a Hyperledger Indy implementation of GraphChain](http://www.graphchain.io/MTSR2018.pdf)
>The main idea behind GraphChain is to use blockchain mechanisms on top of an abstract RDF graphs. This paper presents an implementation of GraphChain in the Hyperledger Indy framework. The whole setting is shown to be applied to the RDF graphs containing information about Legal Entity Identifiers (LEIs).
* [CULedger partners with decentralized identity innovator Evernym to create MyCUID](https://www.cuinsight.com/press-release/culedger-partners-decentralized-identity-innovator-evernym-create-mycuid)
* [Digital Identity Innovator Helps Non-Profits Get on the Identity Blockchain](https://globenewswire.com/news-release/2018/09/25/1575928/0/en/Digital-Identity-Innovator-Helps-Non-Profits-Get-on-the-Identity-Blockchain.html)
>Evernym is opening its Accelerator program to Non Profit Organization (NPOs) applications. Evernym will waive the $50,000 membership fee it normally charges to participate in the program. A panel of judges will select the successful applicants. The first group of awards will be announced before December 2018 and will include 5 organizations. Further NPO cohorts are already planned for 2019.\
>The World Bank estimates over 1 billion persons, usually the most vulnerable, are without formal identity.
* [Cordenity: Evernym and R3 Partner to make Corda compatible with Indy](http://www.paymentsjournal.com/evernym-r3-partner-apply-self-sovereign-identity-financial-services/) [[GitHub](https://github.com/Luxoft/cordentity)] [[Docs](https://schd.ws/hosted_files/hgf18/0e/Indy%20Identity%20on%20R3s%20Corda.pdf)]
* [A Framework for Designing Cryptographic Key Management Systems](https://nvlpubs.nist.gov/nistpubs/specialpublications/nist.sp.800-130.pdf)
* [An Accumulator Based on Bilinear Maps and Efficient Revocation for Anonymous Credentials](https://eprint.iacr.org/2008/539.pdf)
* [An Efficient System for Non-transferable Anonymous Credentials with Optional Anonymity Revocation](https://www.iacr.org/archive/eurocrypt2001/20450093.pdf)
* [Privacy Preserving Authentication—Another reason to care about ZKP](https://www.slideshare.net/eralcnoslen/privacypreserving-authentication-another-reason-to-care-about-zeroknowledge-proofs)
* [Zero-Knowledge Proofs: Privacy-Preserving Digital Identity with Clare Nelson](https://www.slideshare.net/SSIMeetup/zeroknowledge-proofs-privacypreserving-digital-identity-with-clare-nelson)
* [What Zero Knowledge Poof Algorithm is used in Sovrin?](https://forum.sovrin.org/t/what-zero-knowledge-proof-algorithm-is-used-in-sovrin/71/2)
> Our zero-knowledge proofs are part of the [Idemix protocol](http://domino.research.ibm.com/library/cyberdig.nsf/papers/EEB54FF3B91C1D648525759B004FBBB1/%24File/rz3730_revised.pdf), where they are used to prove the possession of [Camenisch-Lysyanskaya credentials](https://eprint.iacr.org/2001/019.pdf). We also use zero-knowledge proofs in the revocation protocol, which is based on [cryptographic accumulators](https://eprint.iacr.org/2008/539.pdf).
* [How is IDEMix Implemented?](https://forum.sovrin.org/t/how-idemex-is-implemented-in-sovrin-indy/)
> Identity Mixer is not directly (re)implemented by Sovrin, but its cryptographic foundations are very similar, and Sovrin’s implementation includes most of its extended features (predicates, multi-credential, revocation, advanced issuance…). One of the researchers who helped to create Identity Mixer is on Sovrin’s Technical Governance Board and has offered insight to keep the implementations aligned on goals and methods.
