Microsoft ION solves Bitcoin-anchored DID infrastructure. H33-74 solves chain-portable evidence for any operational event, of which DID lifecycle is one specific case.
Microsoft ION is an open implementation of the Sidetree protocol, providing decentralized identifiers (DIDs) anchored to Bitcoin. ION's design center is high-throughput DID operations (create, update, deactivate) batched into Bitcoin transactions with off-chain operations resolution via a content-addressable storage layer.
Both projects use Bitcoin as a notarization surface. Both batch operations off-chain and anchor commitments on-chain. Both target enterprise identity and credential use cases.
Microsoft ION is great when the operational concern is decentralized identifier lifecycle in the verifiable credentials ecosystem, when Bitcoin-anchored identity is the design center, and when interoperability with the W3C DID ecosystem is the value.
H33-74 is great when DID lifecycle is one of many operational events needing chain-portable evidence. When post-quantum survivability of identity decisions matters. When the same evidence layer supports identity, compliance, governance, and AI decisions in one consistent format.
Chain portability separates evidence from the infrastructure that produced it.
Chain Portability What Gets Preserved