Re: [DNSOP] EDNS0 clientID is a wider-internet question

Jacob Hoffman-Andrews <> Tue, 25 July 2017 07:51 UTC

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From: Jacob Hoffman-Andrews <>
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Date: Tue, 25 Jul 2017 00:51:04 -0700
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Subject: Re: [DNSOP] EDNS0 clientID is a wider-internet question
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I agree: The EDN0 Client ID draft seems quite bad from a privacy
perspective, and I believe it should not be adopted.

More broadly, enforcing content blocks with DNS is an anti-pattern. If
we're assuming that the entity doing the content blocking has
administrative access to DNS clients, they can simply install content
blockers there. That allows much finer-grained blocked, like blocking
individual pages rather than having to block all of Tumblr because of a
request to block a single page.

The draft even acknowledges the ineffectiveness of DNS-based content

>   DNS filtering products are easy circumvented and should not be
>   considered real security measures.  With commonly available tools it
>   is trivial to discover the non-filtered DNS responses and use them in
>   place of the filtered responses.

So it seems incorrect to propagate a privacy-harming DNS extension that
is ineffective at its stated goals.