DID
https://www.nri.com/-/media/Corporate/jp/Files/PDF/service/ips/technology_1.pdf
ユーザーが自分の情報を管理し、必要な情報だけを必要に応じて提供・連携する
ION, Microsoft
https://hashhub-research.com/articles/2019-09-05-did-overview
DIF: Decentralized Identity Foundation
DID Document a
https://w3c.github.io/did-core/