Re: [arch-d] IAB Statement on Encryption and Mandatory Client-side Scanning of Content

Mallory Knodel <> Mon, 18 December 2023 20:17 UTC

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Date: Mon, 18 Dec 2023 15:17:25 -0500
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To: Brian E Carpenter <>, Andrew Campling <>, George Michaelson <>
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From: Mallory Knodel <>
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Subject: Re: [arch-d] IAB Statement on Encryption and Mandatory Client-side Scanning of Content
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On 12/18/23 2:22 PM, Brian E Carpenter wrote:
> Andrew,
> On 18-Dec-23 23:43, Andrew Campling wrote:
> ...
>> Reflecting further on the IAB statement, I do believe that the lack 
>> of inclusion of a clear definition of client-side scanning within the 
>> IAB's statement is problematic. I suspect that the real issue relates 
>> to the results of that scanning being shared with a third party 
>> without the knowledge of the user rather than the scanning per se.
> The statement is about *mandatory* scanning, which clearly implies 
> that an official third party is involved.
> IMHO, it should be my choice whether my email agent is set up to 
> detect occurrences of "Scunthorpe" in incoming email. Alternatively, 
> it should be my choice whether my mail service provider performs that 
> check for me. But none of this is a protocol issue, or a protocol 
> security issue, so however bad one believes the societal harm to be, 
> I'm at a loss to see why it's an IETF issue.
I just came back here to address the scanning, too. This line that 
client-side scanning "isn't well defined" or "means too many things" is 
just utter smoke and mirrors. Quite the opposite-- because there are so 
many ways to violate a person's civil liberties by breaking into their 
agents and devices means that *all* of them are to be rejected, early 
and often, despite their inner workings.


> The IAB statement is about the effect of specific government 
> requirements that "undermine end-to-end encryption", and that *is* a 
> protocol security issue, so it's a legitimate topic for the IAB and 
> the IETF.
>     Brian
> _______________________________________________
> Architecture-discuss mailing list

Mallory Knodel
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