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  • Updates to the Security and Privacy Considerations
  • Should we have cross-ledger references? eg. a claim-def that references a schema on a different ledger
  • To Do's going forward

Recording from the call: 

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community for all. For more information

please visit the Hyperledger Code of Conduct.

Welcome and Introductions



Collaboration Channels

Agreed Upon:

  • See HackMD Document for most of what we have discussed

Online Discussion (from RocketChat this week)

This Week's Discussion:

  • Notes and Help Wanted from another pass over the hackmd Spec:
    • Help Wanted: Wording of the "namespace" section, with primary and secondary components.
    • Question: Current verkey change does NOT require signature of a new verkey. Should it? No is the concensus.
    • Question: Will it be easy/possible to do "versionTime" query for a DID?
    • Question: Should a "versionId" query require the seqNo be for a NYM, or should it search back on ledger for value of NYM at that time – same as "versionTime"?
    • Question: The new Claim Def DID URL does NOT include the ID of the Schema. That means that you can't have the same named Claim Def using two different Schema. Is that a problem?
      • Nice to have: Analysis of Sovrin MainNet and Sovrin StagingNet to see how many instances of that exist.
    • Question: DID URL Handling for Rev Reg Entries
      • Does not use a straight, request object/return object as with other objects. Instead, may use the RevRegDelta Txn.
      • Good idea?
    • Help Wanted: Security Considerations sections
    • Help Wanted: Privacy Considerations sections
    • DECISION NEEDED: Schema on NetworkB, Claim_Def on NetworkB; NetworkA goes away. Can a holder proof/verify from a credential?
      • Possible: Put a reference on NetworkB to schema on NetworkA
      • Idea: Inter Blockchain Communication Protocol (IBC Protocol) - genesis transaction from NetA on NetB, when write reference to Schema from A to B, can include state proof
        • NetworkB becomes a client of NetworkA
        • CLAIM_DEF MUST reference the local instance of the SCHEMA
        • Extend definition of SCHEMA to include an optional reference to the original schema (DID URL and state proof from other ledgers)
      • Idea: Request that schema owner create a DID on two (or more) networks and write the schema on both networks
        • Leave off the namespace and propose searching multiple ledgers to find schema
      • Idea: Put this as future work?  Put this in as a consideration for issuers.
        • Don't allow for now – future work to enable cross-ledger references
        • Allow but do no extra checking – future work to constrain
      • Idea: Don't allow Claim_Def to reference object on another ledger – schema MUST be on the same ledger.
      • Options:
        1. Do nothing, allow this and ignore the "network can go away" issue.
        2. Do nothing, don't allow this.
        3. Don't allow, but allow some way to have a local copy of the schema.
  • To Do:
    • HackMD Cleanup – another pass
    • Requirements from the DID Core Spec. – 8.1, 8.2, 8.3
    • Convert to SpecUp and publish
    • Create an Indy HIPE that points to the spec.
    • Define the backlog of tasks:
      • indy-node (assuming there is no indy-plenum work)
      • indy-sdk and indy-vdr
      • universal resolver image

Future Discussions: