"gpg: Signature made <date time>" tamper resistant?

[Josef Schneider]

On Mon, Mar 4, 2013 at 4:59 AM, Daniel Kahn Gillmor
<dkg at fifthhorseman.net> wrote:
> Take a look at http://www.itconsult.co.uk/stamper.htm
>
> I have no experience with them, but they've been discussed before in
> this list, if you want to review the archives.
>
> You might also be interested in the relevant wikipedia article:
>
>  https://en.wikipedia.org/wiki/Trusted_timestamping
>
> hth,
>
>         --dkg

Not related to GPG, you might also be interested in
https://www.pki.dfn.de/zeitstempeldienst/ which is AFAIK the only free
"trustworthy" (meaning it is run by a organisation, not a test server
and has some sort of usage terms) RFC 3161 timestamp server.

I use it with PDF signatures (using a certificate issued to me by the
government http://www.buergerkarte.at/), because it is a lot easier to
show average people how Acrobat Reader says everything is OK than
explaining GPG.