> DIDs are fundamentally antithetical to privacy and will only enable a deeper and more obscure level of tracking to all applications that use them. They were originally inspired for mapping public blockchain use-cases, but IMO personal identity and related keys should _never_ be put on a public chain, who thinks this could ever be a good idea or architecture?

Functionally, how different would this be from the status quo? Between the FAANGs basically already having near-universal identifiers for all of us and everyone's information being leaked in a variety of breaches to where it's essentially public knowledge to any black hats or state actors I'm not sure how down the downsides are?

DIDs make use of public key encryption, which does not require storing private data on a public chain to be useful. All that's needed is a public key directory for public entities, everything else can be verified based on said pubkey of those entities who issue credentials

a new identifier (pubkey) can be created for each organization you engage with

OPs argument seems based on imagination has nothing to do with how DIDs are meant to work

Well DID spec doesn't tell us to put identity or related keys in public. DIDs coupled with the VC model (https://www.w3.org/TR/vc-data-model/) allows identity credentials issued by any "trusted" issuer to be validated. Here trusted means whoever the user trusts, be it government or big tech or anything else.

The issue is not other identity information in the DID, it is the identifier mandate itself is antithetical to privacy.

Having a global identifier as you go about the internet means that parties can correlate and share information about you.

Trying to solve that by isolation (using a DID per party you want to interact with) negative affects their usability and privacy properties with verifiable credentials.

Then there ought to be a way tp cheaply produce verified but ephemeral identities, which may be discarded after a particular transaction.

User: I want to use this site.

Site: we need your trusted identity.

User: Trusted Third Party, please make an anonymous identity for me.

TTP: I know you, user; here's your new identity.

User: Site, look here, TTP which you trust says I'm legit.

Site: OK, transaction completed. '

User: (destroys the identity's private key.)

It's not very different from TLS certificates, or OAuth tokens, or even ephemeral credit card numbers. The thing is to have a common Trusted Third Party, and somehow keep the number of such parties large enough.

> The thing is to have a common Trusted Third Party, and somehow keep the number of such parties large enough.

Aye, there's the rub. What's to stop most sites from only allowing Google/Facebook as the Trusted Third Party? And you also need to worry about security breaches, or one company quietly buying up all the independents, or governments legislating in back doors, or every service you use ganging up behind the scenes to try and collate your "anonymous" public keys back into a single identity.

Don't get me wrong, I do think there's a way forward, but it's not going to be easy.

Sounds kind of like LetsEncrypt, but for people.

> User: Site, look here, TTP which you trust says I'm legit.

What does "legit" mean here?

That's a really subtle issue for online identity applications.

It means: "TTP certifies that the user presenting identity X is indeed a user known to me, and is an acceptable user for the purposes that Site asked about: not a bot, not a spammer".

The idea that TTP certifies User against particular requirements of Site, and gives User an identity which User can give to Site. TTP keeps the "real" identity of the user hidden from Site, replacing it with a temporary identity.

TTP does not givel Site anything; User shares the temporary identity with Site. Then Site can check the identity, cryprographically and/or by asking TTP directly.

The identity should also be checked by a challenge-response protocol between Site and User, so that stealing it from User would be pointless. E.g. User keeps the private key and Site receives the public key, and Site asks to encrypt a random string, then tries to decrypt it.

> It means: "TTP certifies that the user presenting identity X is indeed a user known to me, and is an acceptable user for the purposes that Site asked about: not a bot, not a spammer".

How does the TTP know that the user isn't a spammer? Is there a backchannel for reidentifying users in case of abuse allegations? Does the TTP just refuse to issue credentials on behalf of the same user very frequently?

That's incorrect. DID make use of pubkey cryptography to create a new identifier for every entity one operates with... this argument is based on imagination

Where did you get the idea 'global' from? Have you seen Peer DIDs? Most specifications advise you to create limited purpose identities. Use a widely known one when it suits you, like a LinkedIn profile, or Twitter page.

Exactly. DIDs don't need to be global identifiers. I can create multiple DIDs. Maybe one of them gets issued an identity VC. When required I may use that DID to prove my identity, otherwise use the other DIDs.

But what would be the solution? I've already played around with DIDs and Verifiable Credentials in the SSI-context and I like it from a tech perspective. I am also not sure if the spec should be held accountable to potential privacy misuses – the user should be. Additionally, you don't have to use the big tech solutions. The tech is inherently open, just look at the many DID methods.

But what I am concerned of are consortium (identity) networks like Sovrin which are run by a hand full of companies. At least in Germany, the government is starting to like what they are doing which is horrible imo. The identity layer of a state should not be governed by a consortium of private companies, no matter what fancy governance model they have.

> The identity layer of a state should not be governed by a consortium of private companies, no matter what fancy governance model they have.

It’s the same with gaia-x.

The assumption that DID has to be in a public chain is flawed. You should really look at DID use as a mechanism to decentralised the use of certificates. In my mind its definitely not not very different from PKI based certificates or any token based solution like OAuth. The difference is its potential to be decentralised.

DIDs do not specify keys should be written to a public chain, another commented mentioned the VC spec.

Another thing to look at is the did:peer method, it allows you to have a direct connection with a party for secure communication. Either party could root their did against a public key (eg a public organisation) but that is not required.