KILT Protocol receives Web3 Foundation grant for revocable anonymous credentials solution
BOTLabs GmbH, the company behind the KILT Protocol, was awarded grant money for building a blockchain-based revocation feature for Portablegabi, a software library that allows users to present digital credentials anonymously.
Berlin, 1st of April 2020
Web3 Foundation’s grant program selects projects that steward the Web 3.0 ecosystem and primarily focuses on supporting software development related to Polkadot and Substrate. The team behind the KILT Protocol received the grant to further develop the Gabi software library and implement a revocation pallet (Substrate module) — a fully decentralised approach that enables issuers of zero-knowledge credentials to revoke credentials via chain-based accumulators (anonymised white lists).
Portablegabi will provide an easy to use API for signing, verifying and revoking JSON objects (i.e. claims and credentials). The software library — based on the Gabi library which implements Idemix based credentials — includes two important features for securing anonymity: selective disclosure and unlinkability. Selective disclosure enables a user (called Claimer) to choose which specific subset of information in a Credential is available to third parties (called Verifiers). Unlinkability prevents Verifiers from linking two verification sessions of the same Credential together, protecting the identity of the Claimer.
KILT is excited to announce its first milestone: building the revocation pallet to work with Portablegabi. Normally, attesters use blacklists stored on centralised servers to revoke Credentials. Portablegabi provides a scheme to support the revocation of attestations using a distributed ledger.
‘Each attestation contains a non-revocation witness which proves that the attestation is still valid and has not been revoked’, explained Marton Csernai, lead researcher at KILT. ‘Every witness is by default contained inside a mathematical accumulator which is written on a blockchain. If the attester wishes to revoke an attestation, he removes the witness from the accumulator and updates the blockchain with the new accumulator.’
Anonymous revocable credentials are crucial to the privacy and transparency of decentralised ecosystems and enable numerous use cases in the space of decentralised finance. KILT is thrilled to have received this grant from the Web3 Foundation and is looking forward to presenting a tutorial that teaches anyone how to implement the open-source Portablegabi library into their project. Albrecht Weiche and William Freudenberger, the KILT developers who lead the project, presented Anonymous Credentials and discussed the features of portablegabi at the virtual Parity Meetup in Berlin on March 19th.
KILT is an open-source fat blockchain protocol for issuing claim-based verifiable, revocable, and anonymous credentials in the Web 3.0. It provides user data sovereignty and interoperability for applications built on top of it. As only trusted entities can issue useful credentials, KILT has the potential to foster new business models around trust.