Re: [ietf-privacy] Is there an official working definition for Privacy Online?

Stephen Farrell <> Thu, 05 May 2016 13:30 UTC

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To:, Robin Wilton <>, David Singer <>
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Cc: "" <>, Josh Howlett <>
Subject: Re: [ietf-privacy] Is there an official working definition for Privacy Online?
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On 05/05/16 14:20, Dave Crocker wrote:
> On 5/5/2016 1:30 AM, Robin Wilton wrote:
>> Privacy can also be a subjective thing (for instance, some people
>> think it's important to draw their curtains in the evening - others
>> don't). That subjectivity makes privacy a highly contextual thing,
> This is an Alice, Through the Looking Glass perspective on the term.
> At the least, it means it is not a technical term, in which case using
> it in technical contexts is mostly going to cause confusion, since one
> speaker's intended meaning will differ from another listener's...
> Standards work is primarily an exercise in gaining group consensus on
> technical specifics.  If 'privacy' is to be a technical term, then we
> need to agree on its specifics.  That doesn't mean the term needs lots
> of fine-grained detail.  In fact, for something this important and this
> basic, it needs as little detail as possible, while still serving to
> guide technical choices.
>> Privacy is about retaining the ability to disclose data consensually,
>> and with expectations regarding the context and scope of sharing.
> ...
> This looks like an entirely reasonable and helpful definition, as I
> noted a year ago.

It's definitely not bad:-)

I think it misses a bit though, in our context. Sometimes we just
have to expose an identifier (e.g. a source IP address) and that
can be privacy-sensitive, but there's no real way in which it's
consensual, unless one considers even connecting to the network
as consenting in some form to such exposure, which'd be odd I

So while Robin's text is pretty good when I think about payloads,
it doesn't seem to cover issues with meta-data and other protocol
artefacts so well. I'm also not sure how much that'd help when it
comes to considering re-identification issues which can be very
subtle (cf. netflix competition).

But it's a good start.

> There are other, similarly short and focused, definitions. Each is
> reasonable.  And while the differences in the definitions probably
> matter, I think that the need to focus technical work requires choosing
> one.  If we want the term to have useful substance.
> The fact that choosing one has some challenges is being used as a reason
> for not trying.  That's an ironic excuse, for an organization whose
> primary reason for being is the development of community consensus on
> non-trivial choices...

I'd be happy if someone wanted to try craft some definitional text
say in an I-D, with the goal of meeting Dave's challenge to define
privacy in a way that's useful for IETF work. I don't know
if that'd end up as an RFC, but it might, and if well-done, and if
it garnered consensus, it could be quite useful.


> d/