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Re: Implication of building storage around DIDcomm [Was:] DID USER AGENTS

From: Stephen Curran <swcurran@cloudcompass.ca>
Date: Wed, 11 Dec 2019 14:12:36 -0800
Message-ID: <CAFLTOV5EHHaqX0x9z2KbsMBzMbAZfynhc_93u1J8peogBW6Nsg@mail.gmail.com>
To: Orie Steele <orie@transmute.industries>
Cc: Adrian Gropper <agropper@healthurl.com>, Daniel Hardman <daniel.hardman@evernym.com>, Oliver Terbu <oliver.terbu@consensys.net>, W3C Credentials Community Group <public-credentials@w3.org>
I find these answers odd:

> 1. Can DIDComm be used without an agent?
> I think the answer is yes. Can it be used without things that have a DID?
sorta, since any key material can be used to construct a DID via did:peer,
did:key, etc...

DIDComm is a communications/messaging protocol and other than just calling
the "message processing thingy" something other than "agent", it requires

DIDComm is intended to use did:peer (which is a DID) so there is not a
"sorta" there.  I would not call "did:key" a DID, as it is really just a
public key with a transformation to generate an opinionated DIDDoc (which
is a very helpful - it's just not a DID, or at least an extremely
constrained one). DIDComm will likely make use of the did:key method as a
replacement for the conveyance of naked public keys, but I don't think the
DIDComm protocol should ever be implemented based on did:key.  As has been
stated before (but bears repeating) did:peer and did:key are two very
different mechanisms.

DIDComm can use public DIDs and that will be done for certain use cases
(likely on the enterprise side), but will not be the default. That will be

On Wed, Dec 11, 2019 at 1:56 PM Orie Steele <orie@transmute.industries>

> There are a couple questions in here:
> 1. Can DIDComm be used without an agent?
> I think the answer is yes. Can it be used without things that have a DID?
> sorta, since any key material can be used to construct a DID via did:peer,
> did:key, etc...
> 2. Can DIDComm be used with things like ZCaps?
> I think the answer is yes. Consider the case where 2 agents use DIDComm to
> agree to an authorization capability that when invoked grants access to
> some data stored in an encrypted data vault.
> OS
> ᐧ
> On Wed, Dec 11, 2019 at 3:05 PM Adrian Gropper <agropper@healthurl.com>
> wrote:
>> I just read the Aries Agents paper [1] and am trying to process it in the
>> Alice-to-Bob storage context that I work with. [2]
>> Let’s say that the A2A interaction between Alice and Bob is DIDcomm and,
>> if successful, Bob gets a capability to access some storage resource
>> controlled by Alice (that is operated by a different entity than Alice’s
>> agent that issued the capability to Bob).
>> Bob will access the storage resource using a client that is different
>> from the agent Bob used in the A2A / DIDcomm transaction because, in the
>> typical case, Bob’s client is not a fiduciary of Bob and therefore does not
>> fit the Aries definition of agent.
>> The protocol that transfers the capability from Bob’s agent to Bob’s
>> client could be an A2A / DIDcomm transaction. Separately, the protocol that
>> presents the capability to the storage resource could also be an A2A /
>> DIDcomm transaction.
>> Finally, the storage resource then has to verify the capability as being
>> signed by Alice’s agent. If Alice has a DID, then that's probably obvious
>> and DIDcomm would not be involved.
>> The implication of building around the Aries agent definition is that the
>> agents of all four parties (Alice, Bob, Bob's Employer, Storage) would need
>> to deploy DIDcomm.
>> Would this become an adoption problem for SSI? How can we reduce it?
>> -Adrian
>> [1]
>> https://github.com/hyperledger/aries-rfcs/tree/master/concepts/0004-agents/README.md
>> [2]
>> https://docs.google.com/document/d/1FBfs4shirUAtqD_d_t6F6oi2NZ0Y7400MDoYSm14Yco/edit
>> On Wed, Dec 11, 2019 at 7:18 AM Oliver Terbu <oliver.terbu@consensys.net>
>> wrote:
>>> IMO, a DID user agent is not a well-defined term. The community
>>> distinguishes between different types of agents. These agents are either
>>> controlled by an entity, or act on behalf of the entity, run in different
>>> locations and have certain capabilities, e.g., routing messages between
>>> entities, answering to credentials presentation requests on behalf of
>>> entities. I assume you are referring to an agent that runs on a mobile
>>> phone or in the browser (e.g., plugin/extension) that is controlled by an
>>> entity.
>>> In general, there are a lot of companies working in this area and they
>>> have their own agent implementations. The community has agreed so far on
>>> the W3C Verifiable Credentials Data Model (W3C REC) and on the W3C CCG DID
>>> Spec (Community Draft) so far. The DID spec is now being formalized in a
>>> dedicated W3C DID WG. HL Aries/DIF is working on protocols that allows them
>>> to interoperate on the messaging level. The following is a non-exhaustive
>>> list of public edge agents available on Android/ iOS:
>>> - uPort -> https://www.uport.me/
>>> - Evernym/ connect.me -> https://www.evernym.com/products/
>>> - Jolocom -> https://jolocom.io/
>>> - Civic -> https://www.civic.com/
>>> - ...
>>> Oliver
>>> On Tue, Dec 10, 2019 at 5:05 PM Daniel Hardman <
>>> daniel.hardman@evernym.com> wrote:
>>>> If this topic is of interest to you, you may want to read this doc
>>>> <https://github.com/hyperledger/aries-rfcs/tree/master/concepts/0004-agents/README.md>,
>>>> and look at the list of implementations at the bottom
>>>> <https://github.com/hyperledger/aries-rfcs/tree/master/concepts/0004-agents#implementations>.
>>>> This is NOT an exhaustive list of agent technologies; others on the the
>>>> list should chime in with other things, too.
>>>> On Tue, Dec 10, 2019 at 2:49 AM Kenneth Anshewitz <kja10@my.fsu.edu>
>>>> wrote:
>>>>> Hey guys,
>>>>> I'm trying to learn about DIDs and came across your org. I'm
>>>>> interested to know of any emerging DID User agents out there besides
>>>>> potentially Microsoft and BCDiploma. Would Civic be considered a DID user
>>>>> agent?
>>>>> Kenny
> --
> Chief Technical Officer
> www.transmute.industries
> <https://www.transmute.industries>


Stephen Curran
Principal, Cloud Compass Computing, Inc. (C3I)
Technical Governance Board Member - Sovrin Foundation (sovrin.org)

*Schedule a Meeting: **https://calendly.com/swcurran
Received on Wednesday, 11 December 2019 22:12:51 UTC

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