"CertLedger: A New PKI Model with Certificate Transparency Based on Blockchain" (2018) https://arxiv.org/pdf/1806.03914 https://scholar.google.com/scholar?q=related:LF9PMeqNOLsJ:sc...
"TABLE 1: Security comparison of Log Based Approaches to Certificate Management" (p.12) lists a number of criteria for blockchain-based PKI implementations:
- Resilient to split-world/MITM attack
- Provides revocation transparency
- Eliminates client certificate validation process
- Eliminates trusted key management
- Preserves client privacy
- Require external auditing
- Monitoring promptness
... These papers also clarify why a highly-replicated decentralized trustless datastore — such as a blockchain — is advantageous for PKI. WoT is not mentioned.
"Blockchain-based Certificate Transparency and Revocation Transparency" (2018) https://fc18.ifca.ai/bitcoin/papers/bitcoin18-final29.pdf
https://scholar.google.com/scholar?q=related:oEsKmJvdn-MJ:sc...
Who can update and revoke which records in a permissioned blockchain (or a plain old database, for that matter)?
Letsencrypt has a model for proving domain control with ACME; which AFAIU depends upon DNS, too.