Self-Sovereign Identity (SSI) is a model of digital identity where individuals own and control their personal data – holding verifiable credentials from trusted entities, storing them in a personal digital wallet, and selectively disclosing only necessary information. SSI eliminates the need for centralised identity providers (Google, Facebook, governments) as intermediaries for every digital interaction. The SSI architecture: Issuers (universities, employers, governments) issue verifiable credentials to user wallets; Holders store credentials in decentralised identity wallets (digital passports); Verifiers (websites, protocols, employers) request and verify specific credentials without accessing the underlying data store. Key standard: Decentralised Identifiers (DIDs) – a W3C standard for blockchain-anchored identity without central registries. In crypto, SSI enables KYC that preserves privacy (prove you are over 18 without sharing your birthdate), non-transferable reputation (soulbound tokens as verifiable credentials), and cross-platform identity without platform lock-in. Projects building SSI infrastructure include Ontology, Civic, Ceramic Network, and Ethereum ENS combined with ERC-725.
Example: Example: Instead of uploading your passport to every crypto exchange, you hold a government-issued digital credential in your SSI wallet. When Binance requests KYC, you share only a zero-knowledge proof that you are over 18 and not on a sanctions list – no name, no address, no ID number shared. Binance receives cryptographic confirmation of compliance; you maintain full data sovereignty.
Learn more: W3C – Decentralised Identifiers
