DID: Decentralized Identifier or Decentralized Identity?

2 August 2021 | Digital identity, News, Tips

Sophie Dramé-Maigné

DID: Decentralized Identifier or Decentralized Identity?

The world of digital identity is full of new concepts and even newer terms. It can sometimes be hard to navigate this lexicon, especially when acronyms are thrown into the mix. A term that keeps popping up recently is DID. But what is it and what does it stand for?

Depending on who is using it, DID can be used to refer to three things:
1. a Decentralized IDentity,
2. a Decentralized IDentifier,
3. a specific standard for Decentralized Identifiers

Let’s dive in!

Decentralized Identities: Did you mean SSI?

Decentralized Identities: Did you mean SSI?

When we refer to decentralized identities, what do we mean? Decentralized identities are constructed in contrast to siloed or federated identities. Siloed (aka centralized) identities are controlled by the service provider that generates them. A given user requires one siloed identity by service it uses. Federated identities introduce a new actor: the identity provider.

It reduces the number of separate identities required by enabling one identity to be used with several service providers. In both cases however, the identity is owned by a single entity, either the service provider or the identity provider. If this entity ceases to exist, so does the identity.

self-sovereign identities (SSI)

Unikname’s Decentralized IDentifier: the UniknameID

Decentralized identifiers are the first step towards decentralized identities. In order to use something, you must first be able to designate and reference it. And to designate a SSI, you need decentralized identifiers. For its identifier, Unikname has chosen to focus on human-readability.

At Unikname, we believe in usability. As a leverage for adoption, innovation, and even better security. The physical and the digital are intertwined. Just like domain names are used to represent websites instead of their IP address, SSI needs a human-readable identifier to exist outside of the digital space.

The UniknameID is Unikname’s decentralized identifier. A UniknameID is:

  1. Human-readable,
  2. Unique,
  3. Immutable,
  4. Obfuscated,
  5. Self-Sovereign,
  6. Durable.

DID: an emerging standard

Self-Sovereign Identities come with an interoperability imperative. The Decentralized Identity Foundation (DIF), in collaboration with the W3C, has been working on standards that would enable built-in interoperability. The first such standard is the DID.

In this standard, a DID is a specific type of decentralized identifier that refers to any subject, be them an individual, an organization, an object, an animal, or even an abstract concept.

DID: an emerging standard

Looking closer, a DID is a string of characters with a very specific format. A DID is made up of three parts, separated by colons: a fixed prefix, the DID method, and a method-specific identifier. All DID begin with the same three characters: did. This is a fixed prefix that tells a parser that it is about to read a DID. After that, comes the method.

There are already over 100 published DID methods. Unikname has published two of them. Each method describes how DID are generated and updated, how they can be shared and resolved. A method also defines what their method-specific identifier looks like.

Different method may generate DID based on different networks (i.e. Bitcoin, Ethereum, Unikname Network, etc). They may use different methods to generate identifiers or refer to different types of subjects (i.e. a smart contract, a NFT, a blockchain address, etc). The DIF provides a registry for existing DID methods.

In Conclusion

So in the end, what is a DID? It can be all three of these things. But to make it simple on all of us:

  • When referring to decentralized identities, use SSI; 
  • When referring to Unikname’s decentralized identifier, use UniknameID;
  • When referring to the DIF and W3C standard, go ahead and use DID.

Want to go deeper? To learn more about SSI and why we need them, read our article on the subject. To learn everything about the UniknameID, consult the Unikname’s website. And stay tuned for a more technical presentation of DID. Coming soon!