US 12,445,288 B2
Multi-issuer anonymous credentials for permissioned blockchains
Kaoutar El Khiyaoui, Zurich (CH); Angelo De Caro, Zurich (CH); and Elli Androulaki, Zurich (CH)
Assigned to International Business Machines Corporation, Armonk, NY (US)
Filed by International Business Machines Corporation, Armonk, NY (US)
Filed on Dec. 13, 2021, as Appl. No. 17/644,091.
Prior Publication US 2023/0188353 A1, Jun. 15, 2023
Int. Cl. H04L 9/32 (2006.01); H04L 9/00 (2022.01); H04L 9/30 (2006.01); H04L 9/40 (2022.01)
CPC H04L 9/3221 (2013.01) [H04L 9/30 (2013.01); H04L 9/50 (2022.05); H04L 63/0421 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A system comprising:
a memory; and
a processor in communication with the memory, the processor being configured to perform processes comprising:
obtaining, by a node on a blockchain network, credentials for a user of the blockchain network from an issuer, the credentials based on one or more attributes of the user,
wherein the issuer is selected from a plurality of authorized issuers for the blockchain network, and
wherein the credentials include a first signature on the one or more attributes and a secret key;
generating, by the node, an operation composed of a payload and a second signature;
computing, by the node, a commitment to a public key of the issuer;
proving, by the node using a one-out-of-many proof, that the commitment is a valid commitment to a public key of one of the plurality of authorized issuers;
proving, by the node using a zero-knowledge proof, proof of knowledge of the first signature and the credentials under the public key of the issuer; and
proving, by the node, using a proof of knowledge of values of the signed secret key and the one or more attributes to grant the user access without revealing an identity of the user.