HashLinkSSI, SignedHashLinkSSI (RFC-015)

Document Maintainers: Andi Gabriel Tan 2024. List of other contributors in Annex. 1.

Copyright: MIT license

Copyright © 2018-2024 Axiologic Research and Contributors.

This document is licensed under MIT license.


Bricks’ content is encrypted using the encryption key of an external secret KeySSI, such as the SReadSSI. The hash that is returned is used to create a HashLinkSSI. The owners of the DSU (i.e. owning a SeedSSI) or other users that got access to a derived SReadSSI can find and decrypt the bricks.

Figure 1: SSIs that do not need anchoring and resolve to immutable DSUs

1. HashLinkSSI description with examples

Type Purpose and description
hl Owning a HashLinkSSI provides no access unless accompanied by an “external secret”.

2. Specific parameters for HashLinkSSI subtypes

Type Type Specific Identifier Hash function Control Key Encryption Hint description
hl Brick hash sha256 empty with AES: external key. IP of your favorite brick storage.

Table 1: HashLinkSSIs algorithms

3. HashLinkSSI family-specific functions

Function HashLinkSSI.initialize(dlDomain, array, vn, hint)

Description: Initialize a WalletSSI with your own parameters.

Name Type Value Description
dlDomain string *required The blockchain domain wanted to be used.
array string *required The array will be used in the initialization to get the final specific string of your HashLinkSSI.
vn (optional) string   The version number of the SeedSSI you want to use.
Default value: “v0”.
hint (optional) string   Optional information for the keySSI resolver.
Default value: undefined.

Function HashLinkSSI.derive()

Description: Exists in mixings but does not have a valid semantic for Hash Link SSIs.

Function HashLinkSSI.getTypeName()

Description: Returns the type of the SSI.


Name Description
SSITypes.HASH_LINK_SSI A string representing the type of the SSI.

Function HashLinkSSI.getHash()

Description: Returns the actual hash of the brick.


  1. Axiologic Research: New content and improvements. Original texts under PharmaLedger Association and Novartis funding. MIT licensed content accordingly with the contracts. Publish and maintain the www.opendsu.org site.

  2. PharmaLedger Project: Review, feedback, observations, new content, and corrections MIT licensed accordingly with the consortium agreements.

  3. PrivateSky Research Project: MIT licensed content accordingly with the contracts. https://profs.info.uaic.ro/~ads/PrivateSky/

Annex 1. Contributors

Current Editors Email
Sînică Alboaie sinica.alboaie@axiologic.net
Cosmin Ursache cosmin@axiologic.net
Teodor Lupu teodor@axiologic.net
Andi-Gabriel Țan andi@axiologic.net
Contributors Axiologic Research Email
Adrian Ganga adrian@axiologic.net
Andi-Gabriel Țan andi@axiologic.net
Cosmin Ursache cosmin@axiologic.net
Daniel Sava daniel@axiologic.net
Nicoleta Mihalache nicoleta@axiologic.net
Valentin Gérard valentin@axiologic.net
PrivateSky Contributors Email
Alex Sofronie alsofronie@gmail.com (DPO)
Cosmin Ursache cos.ursache@gmail.com (UAIC)
Daniel Sava sava.dumitru.daniel@gmail.com (HVS, AQS)
Daniel Visoiu visoiu.daniel.g@gmail.com (SGiant)
Lenuța Alboaie lalboaie@gmail.com (UAIC)
Rafael Mastaleru rafael@rms.ro (RMS)
Sînică Alboaie salboaie@gmail.com (UAIC)
Vlad Balmos vlad.balmos@gmail.com (Code932)
PharmaLedger Contributors Email
Ana Balan bam@rms.ro (RMS)
Bogdan Mastahac mab@rms.ro (RMS)
Cosmin Ursache cos@rms.ro (RMS)
Rafael Mastaleru raf@rms.ro (RMS)