[OAUTH-WG] Sharing a client_id: is it good or bad ?

Sergey Beryozkin <sberyozkin@gmail.com> Wed, 04 November 2015 16:01 UTC

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From: Sergey Beryozkin <sberyozkin@gmail.com>
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Date: Wed, 04 Nov 2015 16:01:16 +0000
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Subject: [OAUTH-WG] Sharing a client_id: is it good or bad ?
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Hi All

I'm having a discussion with my colleagues on the pros and cons of 
sharing a client_id.

For example, say we have N number of public mobile applications (the 
same application package, an application instance on an individual 
phone), and one approach is for each of these applications to have the 
same client_id.

I've been trying to analyze why it can be bad and the only thing I can 
come up with is that there will be no (easy) way to track which 
application instance actually accessed a given RS.

Can someone please explain what the pros and cons are of having the same 
client_id shared between public client applications.

And what about multiple confidential clients being set up with the same 
id/secret. I suspect it is a bad idea but what is main line why it is a 
bad idea, lets say it is all done in the protected network, no chance of 
the bad clients interfering...

Thanks, Sergey