Summary of Gordian Meeting @ November 6, 2024

[shannona]

November Meeting

November 6 was the Blockchain Commons identifier meeting, focusing on three major presentations:

• XIDs
• Edge Identifiers & Cliques
• MuSig & GSTP

XIDs (Presentation One)

Extensible Identifiers

We need identifiers that are more privacy respecting!

• Still in its early stages
• early research

See our early draft working document on XIDs.

XIDs

• decentralized!
• use Gordian Envelope

A 32-byte unique identifier

• with XID CBOR tag (40024)
• CBOR structure adds 5 byte (d9 / 9c58 / 5820)
• A XID can be Identified for user visually with first 4 bytes.
  • (Or Lifehash or ByteWords or even emojis!)
• Can be packaged as a UR

Resolving a XID

Resolution Not built into XID

• Though universal resolvers should help

But you can also include resolution methods in a Gordian Envelope

• with XID as subject
• derefenceVia

A Xid with a dereferenceVia is still a XID document!

• can be encoded as ur:xid
• Allows XID to be self-describing

Creating a XID

Start with a key pair

• This is the inception key

Encode it to CBOR

Take the SHA-256 digest of the CBOR

That's a XID!

You can show public key

• demonstrates uniqueness
• demonstrates randomness

XID Document

A XID Document includes

• XID
• public key
• signature made by inception key

Can also include:

• Resolution methods
  • Allows discovery of whole revision history
• Signing & encryption keys
• permission delegation
  • deny-first permission structure
  • keys with fine-grained permissions
• Endpoints
• Provenance Marks

Eliding a XID Document

You can elide a XID Document for a specific purpose!

• Minimal Disclosure
• Could elide all the way down to just key & signature
• But signature still verifies

What are the Uses?

New decentralized identifier

• with elision!
• Create new secure credentials & entitlemenes

Many other use cases

• NOSTR: rotate keys, share reputation signals, etc
• Record provenance of digital assets

The provenance ability allows us to to avoid some of the problems with Bitcoin/blockchains of unintended correlation

Edge Identifiers & Cliques (Presentation Two)

Single Signature Paradigm is the old way to do things

• one private key, one public key, one identifier
• 50 years old!

It's dangerous: Single Points of Compromise, Failure

• Also dangers of fragility, bitrot, more
• They're not theoretical! See #SmartCustody's adversaries

We want to create a new model where identity is based on relationships

• That was the basis of Self-Sovereign Identity
• Because identity is inherently decentralized!

Your "relational edges" form your connections with others

• Schnorr gives us the ability to create these relational edges
• Two parties create a joint key, with the key only existing in the cryptographic "fog"
• Group sigs are indistinguishable from a single signature under Schnorr!
• Public key is identifier for edge

The next step: identifiers for entire groups

• closed cliques
• simplest is "triadic"
• Edge identifier between every pair in group
• Public & Private key for clique created by edges
• Can go higher order

Can also have:

• cliques of cliques
  • More flexible identity management!

Advantages

• Decentralized
• Peer-based validation of identity
• SPOF/SPOC resilience
• Secret group decision making
• Enhanced privacy

Drawbacks

• Complex, new
• No instant gratification

Other cliques

• Open Cliques
• Fuzzy Cliques (FROST)
• Cliques with Devices

Final Notes

• We need identity models that support relationships
• We need to support groups that support us!

Articles:

• Edge Identifiers & Cliques
• Open & Fuzzy Cliques

Making MuSig

See MuSig Sequence Diagrams for more.

MuSig is powerful because of its scalability, efficiency, security, privacy, and accountability

• See BIP 327

Creating a 2-of-2 MuSig is trivial, but 3-of-3 is harder.

GSTP can help!

• GSTP wraps messages
• So that only intended recipient decrypt
• Help from Enscapsulated State Continuation (ESC)

Allows a 3-of-3 with a trustless coordinator who does not access sensitive data!

• Routes in a trustless fashion

Next Meeting: December 4th

FROST for Wallet Develoeprs!

Join subscriber list for more info.