On Thu, 2020-05-21 at 13:57 +0200, Ulrich Mueller wrote:
> > > > > > On Thu, 21 May 2020, Robert Bridge wrote:
> > On Thu, 21 May 2020 at 09:47, Michał Górny <mgorny@gentoo.org> wrote:
> > > Option 1: IP-based limiting
> > > ===========================
> > > 
> > Preface this with IANAL, check with your own legal counsel...
> > While IP address based methods might be attractive  technically, do
> > remember that an IP address is considered Personally Identifiable in
> > European Data Protection law.
> > The fact submissions require an action by the user will probably be
> > sufficient to be explicit consent, any system storing these details should
> > allow for the use to revoke their consent: If you collect anything
> > personally identifiable, you will need to provide a mechanism for users to
> > request the removal of all their submissions.
> > Tread carefully with this project. :)
> 
> You don't have to store any IP addresses, you can store a cryptographic
> hash like their b2sum (salted if necessary).
> 

Yes, this is as great as storing hashes of phone numbers ;-).

-- 
Best regards,
Michał Górny