This credential format was created specifically to leverage the CL Signatures. JSON-JWT and JSON-LD Signatures each have their own way of representing the meaning of the attributes within a VC. JSON-JWT references an IANA registry and assumes a “closed world” authority model based on that authoritative registry. JSON-LD Signatures use an @context field to reference existing RDF mapping to known dictionaries and assumes an open world model where new terms and definitions can easily be introduced
* [Verifiable Credentials Flavors Explained](https://www.lfph.io/wp-content/uploads/2021/02/Verifiable-Credentials-Flavors-Explained.pdf) 2021 CCI Kaliya 'Identity Woman' Young
> ZKP-CL: This credential format was created specifically to leverage the [CL Signatures](https://link.springer.com/chapter/10.1007/3-540-36413-7_20). JSON-JWT and JSON-LD Signatures each have their own way of representing the meaning of the attributes within a VC. JSON-JWT references an IANA registry and assumes a “closed world” authority model based on that authoritative registry. JSON-LD Signatures use an @context field to reference existing RDF mapping to known dictionaries and assumes an open world model where new terms and definitions can easily be introduced
* [Wrapping Indy Credentials (AnonCreds) in W3C VCs](https://hackmd.io/S6e2MeSWTICnV9lD9OukKg) 2021-04-12
> AnonCreds are typically bound to a holder by using a link secret and not by issuing a credential to a public DID. In order to add such a credential (or a subset of attributes) to the public profile, we suggest the following mechanism which expresses the intent: I self-attest that I have this credential with the specific attribute values, if you require a proof you can ask me using the Aries present proof protocol.
* [Anonymous Credential Part 2: Selective Disclosure and CL Signature](https://medium.com/finema/anonymous-credential-part-2-selective-disclosure-and-cl-signature-b904a93a1565) 2021-02-04
> selective disclosure and an anonymous credential (Anoncred) relies on an efficient signature scheme that supports multiple messages with a single signature. One such signature scheme is known as CL signature that is named after its Jan Camenisch and Anna Lysyanskaya […] CL signature popularized Anoncreds, and it also served as a cryptographic building block in Identity Mixer (Idemix) and Hyperledger Indy projects.
* [Anonymous Credential Part 1: Brief Overview and History](https://medium.com/finema/anonymous-credential-part-1-brief-overview-and-history-c6679034c914) 2020-10-01
> An anonymous credential (Anoncred), which is also known as an attribute-based credential (ABC), is a concept for a digital credential that provides a credential holder maximal privacy and an ability to selectively disclose their personal information.
* [CL Signatures for Anonymous Credentials](https://blog.goodaudience.com/cl-signatures-for-anonymous-credentials-93980f720d99) 2019-01-14 Will Abramson
> A CL Signature is a signature scheme developed by Jan Camenisch and Anna Lysyanskaya. This scheme has some properties that make it ideal for use in an anonymous credential system and is, in fact, the scheme that Sovrin, and I am sure others, currently use. In this post, I will try to synthesise my current understanding of this scheme, including a look at how Sovrin uses it in practice.
* [Attribute Based Credentials and Variable Length Data Graphs](https://github.com/WebOfTrustInfo/rwot6-santabarbara/blob/master/topics-and-advance-readings/AttributeBasedCredentials_and_VariableLengthDataGraphs.md) 2018-02-28
> Attribute Based Credentials using Camenisch Lysyanskaya signature schemes typically require a fixed list of attributes defined before issue time in order to validate the correct attribute signature for revealed and unrevealed attributes, including predicate proofs. This poses problems when an attribute based credential system is to be used for arbitrary data graphs or schema definitions with optional fields, multi-valued fields or nested data structures, such as data schemas in wide use, documented on sites like schema.org.
>
> In an effort to allow JSON-LD data structures to leverage attribute based credentials and zero knowledge signature schemes, this paper outlines differences, requirements and possible options for representing JSON-LD data in attribute based credential schemes such as the one in use by the Sovrin network, implemented in the Hyperledger Indy project.
* [Literature] [A Signature Scheme with Efficient Protocols](https://cs.brown.edu/people/alysyans/papers/camlys02b.pdf)
Jan Camenisch IBM Zurich, Anna Lysyanskaya Brown
> Digital signature schemes are a fundamental cryptographic primitive, of use both in its own right, and as a building block in cryptographic protocol design. In this paper, we propose a practical and provably secure signature scheme and show protocols (1) for issuing a signature on a committed value (so the signer has no information about the signed value), and (2) for proving knowledge of a signature on a committed value. This signature scheme and corresponding protocols are a building block for the design of anonymity-enhancing cryptographic systems, such as electronic cash, group signatures, and anonymous credential systems. The security of our signature scheme and protocols relies on the Strong RSA assumption. These results are a generalization of the anonymous credential system of Camenisch and Lysyanskaya
