Crypto Gloss

Decentralized Identity

Digital identity today is controlled by corporations: your Google account, Apple ID, or Twitter handle can be revoked at any time, cannot be transferred, and gives the platform complete visibility into your activity. Decentralized identity (DID — both the movement and the specific W3C standard) proposes an alternative: identity credentials anchored in cryptographic keys you control, attestations from trusted parties recorded on-chain or in decentralized storage, and social graphs owned by the user rather than the platform. In crypto, this movement spans multiple layers: domain names (ENS), protocol-level social graphs (Lens, Farcaster), formal credentialing systems (Verifiable Credentials, W3C DIDs), sign-in standards (SIWE), and reputation primitives tied to wallets (Soulbound Tokens). Each addresses a different dimension of the identity problem; together they sketch a web3 identity stack.

The Identity Problem in Web2 vs. Web3

Web2 identity:

  • Platform-controlled: Facebook, Google, Twitter are identity gatekeepers
  • Cross-platform portability: minimal (OAuth allows login, not data portability)
  • Censorship: accounts can be deplatformed
  • Privacy: platform harvests all activity data
  • Sybil resistance: accounts are expensive enough to create friction but not truly sybil-resistant

Blockchain identity:

  • Address = pseudonymous identity (0x7a23…b4c2)
  • Fully pseudonymous by default — not tied to legal identity
  • Portable: same address works on every EVM chain
  • Censorship-resistant: no one can prevent a wallet from transacting
  • Problem: addresses are hard for humans to remember, have no social context, and carry no reputation signal

The gap: Blockchain addresses are too low-level for human interaction; web2 identity is too centralized. Decentralized identity systems try to bridge this.

ENS — Ethereum Name Service

ENS converts cryptographic Ethereum addresses into human-readable names:

  • .eth domains (vitalik.eth → 0xd8dA6…3047)
  • Stored as NFTs on Ethereum; owner controls resolution
  • Reverse resolution: an address says “I am vitalik.eth”
  • Subdomains: workspace.vitalik.eth for organizational hierarchy
  • Text records: can store avatar, Twitter handle, email, website

Extension: ENS supports multi-chain — a .eth name can resolve to Bitcoin, Solana, and other chain addresses simultaneously.

ENS Token: Governance token for the ENS DAO; controls protocol parameters and treasury.

Non-ENS alternatives:

  • Unstoppable Domains (.crypto, .nft domains): Polygon-based; one-time purchase (no renewal fees)
  • Lens handles: @username.lens — social identity (below)
  • Farcaster FIDs: Numeric IDs with usernames

Lens Protocol

Lens is an on-chain social graph protocol on Polygon:

  • Profile NFT: Your Lens profile is an NFT you own; it holds your followers, publications, and social graph
  • Follow NFTs: When someone follows you, they receive a Follow NFT
  • Collect NFTs: Publications can be “collected” — monetization built in
  • Mirror: Equivalent of retweet; creates on-chain records of content propagation

Why “open social graph” matters:

  • Any app built on Lens can access the same social graph
  • If Lens app A bans you, your followers and content still exist — you take them to app B
  • Platform competition on UI/UX rather than data lock-in

Lens apps: LensFrens (social discovery), Phaver, Orb (mobile), Hey (web client)

V2 and Lens Chain: Lens launched V2 with improved modules and a plans for Lens Chain — a dedicated ZK rollup for social applications.

W3C DIDs and Verifiable Credentials

DID (Decentralized Identifier) is a W3C standard (finalized 2022):

  • URN-style identifier: did:ethr:0x7a23...b4c2 or did:key:... or did:ion:...
  • Resolves to a DID Document containing public keys and service endpoints
  • Self-sovereign: owner controls the DID document (can rotate keys, add services)
  • Method-specific: did:ethr anchors to Ethereum; did:ion anchors to ION (Bitcoin-based); did:web anchors to a domain

Verifiable Credential (VC):

  • A cryptographically signed statement from an issuer about a subject
  • “Johns Hopkins University” signs a credential: “Alice holds a Ph.D. in Computer Science”
  • Alice stores this credential in her wallet
  • Alice presents it to a verifier who checks the signature without calling a central database
  • Privacy-preserving: Alice can share selective disclosure (“I have a degree” without revealing which university)

Decentralized identity stack:

  1. Identifier layer: DID (the “address” of your identity)
  2. Attestation layer: Verifiable Credentials (what others say about you)
  3. Wallet layer: DID wallet (stores credentials, signs presentations)
  4. Verification layer: API/contract that checks signatures

SIWE — Sign-In With Ethereum

SIWE (EIP-4361) is the web3 equivalent of “Sign in with Google”:

  • Instead of OAuth, a website challenges you to sign a message with your Ethereum wallet
  • Signature proves you control the address (no password required)
  • User experience: MetaMask/Rainbow pops up → sign → authenticated
  • Privacy: session token issued by the site, but the wallet signature is the authentication proof

Adopted by: ENS App, OpenSea, Rainbow, many dApps

CAIP-122: Extends SIWE to other chains (Solana, Bitcoin) via a chain-agnostic standard

Security note: SIWE message should include nonce (prevents replay), expiration, and site URI. Users should verify they’re signing on the intended site.

Soulbound Tokens (SBTs)

SBTs are non-transferable NFTs — inspired by Vitalik Buterin’s “Decentralized Society” paper (2022):

  • Bound to a “Soul” (address); cannot be sold or moved
  • Represent credentials, achievements, affiliations that should be tied to identity
  • Examples: proof of attendance, college degree, professional certification, credit history

Gitcoin Passport:

  • Aggregates multiple identity attestations (Google, GitHub, ENS, BrightID, Twitter)
  • Generates a “Passport Score” — a sybil-resistance score
  • Used by Gitcoin Grants (quadratic funding): higher passport score = more grant matching
  • Open standard: any protocol can use Gitcoin Passport for sybil resistance

Attendance tokens (POAPs):

  • Proof of Attendance Protocol — NFTs issued for attending events
  • Build a verifiable record of in-person or on-chain participation

Proof of Humanity and BrightID

For systems where you need to prove “one person, one account”:

BrightID:

  • Social graph-based identity: you attend verification parties where humans verify each other
  • Creates a trust graph; BrightID score = number of trusted connections
  • Used by Gitcoin Grants, HumanityDAO for airdrop eligibility

Proof of Humanity:

  • Video submission + deposit + vouching from existing PoH users
  • Creates a list of verified humans on Ethereum
  • Sybil-resistant: each human appears once; deposit deters false submissions

Worldcoin (biometric):

  • Iris scan via “Orb” device → generates ZK proof of unique humanness
  • No biometric data stored (only iris hash); privacy-preserving by design
  • Fastest growing uniqueness list; controversial (biometric consent, centralized Orb hardware)

Attestation Standards

EAS (Ethereum Attestation Service):

  • On-chain attestation registry on Ethereum, Base, and other chains
  • Any address can make attestations about any other address
  • Schema registry: attestation structures (schemas) are public and reusable
  • Used by: Coinbase for on-chain identity (Coinbase Verified), OP Stack for RetroPGF attestations

Social Media Sentiment

Decentralized identity is seen as a foundational infrastructure layer that crypto has not yet “solved.” ENS is considered the most successful deployed piece — millions of .eth names registered, universal recognition in the Ethereum community. Lens Protocol adoption has been slower than hoped, with the social graph use case not yet creating a compelling enough reason to move from Twitter/X. Verifiable Credentials and DIDs are gaining traction in enterprise and government identity contexts (EU digital identity wallet uses VC technology) but remain niche in crypto. The strongest near-term momentum is around attestations (EAS) and identity scores (Gitcoin Passport) for specific DeFi applications like airdrop eligibility and quadratic voting. The long-term vision — portable on-chain identity that replaces Google login and eliminates platform censorship risk — remains compelling but multi-year work.

Last updated: 2026-04

Related Terms

Sources

Reed, D., Sporny, M., Longley, D., Allen, C., Grant, R., & Sabadello, M. (2022). Decentralized Identifiers (DIDs) v1.0. W3C Recommendation.

Sporny, M., Longley, D., Sabadello, M., & Burnett, D. (2022). Verifiable Credentials Data Model v1.1. W3C Recommendation.

Weyl, E. G., Ohlhaver, P., & Buterin, V. (2022). Decentralized Society: Finding Web3’s Soul. SSRN Working Paper.

Kim, S., & Maul, T. (2020). A Study on the Decentralized Identity and Access Management Systems. IEEE Access.

Faber, B., Broere, J., Hofman, W., & van der Laak, A. (2019). Privacy-Preserving Verification Against Attribute-Based Credentials. Lecture Notes in Computer Science, 11737.