!!! Overview
[{$pagename}] ([CL Signature] Camenisch-Lysyanskaya) are a form of [Digital Signature] invented by Jan Camenisch and Anna Lysyanskaya in [2001|Year 2001]. 

In addition to being secure [Digital Signatures], they need to allow for the efficient implementation of two [protocols]:
* A protocol for computing a [Digital Signature] in a secure two-party computation protocol.
* A protocol for proving knowledge of a [Digital Signature] in a [Zero-knowledge proof] protocol.
In applications the first [protocol] allows a signer in possession of the signing [key], to issue a [Digital Signature] to a user (the signature owner) without learning all the [messages] being signed or the complete signature.

The second [protocol] allows the signature owner to prove that he has a signature on a number of [messages], without revealing the [Digital Signature] and only a (possibly) empty subset of the [messages].

The combination of these two [protocols] allows for the implementation of digital credential and [ecash] [protocols].

[{$pagename}] may have [United States] and other country [Patents] [{$pagename}] is a form of a [Group Signatures]

[{$pagename}]s have been enhanced since the original.

!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]
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* [#1] - [Signatures_with_efficient_protocols|Wikipedia:Signatures_with_efficient_protocols|target='_blank'] - based on information obtained 2018-10-28- 
* [#2] - [Revocation of anonymous certificates, credentials, and access rights|https://patents.google.com/patent/US7543139|target='_blank'] - based on information obtained 2018-10-28- 
* [#2] - [ 
A Signiture with Efficient Protocols|https://groups.csail.mit.edu/cis/pubs/lysyanskaya/cl02b.pdf|target='_blank'] - based on information obtained 2019-01-17-