Re: [OAUTH-WG] updated Distributed OAuth ID

Torsten Lodderstedt <> Tue, 24 July 2018 20:47 UTC

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From: Torsten Lodderstedt <>
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Date: Tue, 24 Jul 2018 22:47:07 +0200
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To: Dick Hardt <>
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Subject: Re: [OAUTH-WG] updated Distributed OAuth ID
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For every bank (and their customers) there is a set of services run by the bank or other entities, which rely on the AS of the particular bank for authorization. In some cases, a service may bring its own AS to the party (due to technical restrictionions). So an RP binding to a certain bank-specific service ecosystem needs to determine which AS every RS relies on. Authorization requests for RS relying on the same AS (the bank) can be combined into s single request/flow resulting in an optimized UX.

> Am 24.07.2018 um 22:21 schrieb Dick Hardt <>om>:
> I'm trying to understand the use case. 
> It still is vague. Are you saying that each of these is run by a different entity, but all trust the bank as the authorization server to manage if the user has granted permission to use the resource rather than managing it themselves? 
> account information, payment initiation, identity, and electronic signature 
>> On Tue, Jul 24, 2018 at 8:59 AM, Torsten Lodderstedt <> wrote:
>>> And who is the AS?
>> In case of yes, it’s typically the bank. At Deutsche Telekom, it is the central AS/IDP. 
>> Why are you asking?
>>>> On Mon, Jul 23, 2018 at 12:50 PM, Torsten Lodderstedt <> wrote:
>>>>> Am 23.07.2018 um 13:58 schrieb Dick Hardt <>om>:
>>>>> In your examples, are these the same AS?
>>>> yes
>>>>>> On Mon, Jul 23, 2018 at 3:42 AM Torsten Lodderstedt <> wrote:
>>>>>> Hi Dick,
>>>>>> > Am 23.07.2018 um 00:52 schrieb Dick Hardt <>om>:
>>>>>> > 
>>>>>> > Entering in an email address that resolves to a resource makes sense. It would seem that even if this was email, calendar etc. -- that those would be different scopes for the same AS, not even different resources. That is how all of Google, Microsoft work today.
>>>>>> I don’t know how those services work re OAuth resources. To me it’s not obvious why one should make all those services a single OAuth resource. I assume the fact OAuth as it is specified today has no concept of identifying a resource and audience restrict an access token led to designs not utilizing audience restriction. 
>>>>>> Can any of the Google or Microsoft on this list representatives please comment?
>>>>>> In deployments I‘m familiar with email, calendar, contacts, cloud and further services were treated as different resources and clients needed different (audience restricted) access tokens to use it.
>>>>>> In case of YES, the locations of a user’s services for account information, payment initiation, identity, and electronic signature are determined based on her bank affiliation (bank identification code). In general, each of these services may be provided/operated by a different entity and exposed at completely different endpoints (even different DNS domains).
>>>>>> kind regards,
>>>>>> Torsten.