I don't fully understand the model that excludes GPS data as a
provider of a "specific place". Would the GPS satellites and ground
units be an "external" data source? If so, is your assertion that GPS
data from a device's logging app could be forged in transit?

-lee

On Mon, Aug 26, 2013 at 8:12 PM, Rich Jones <rich@openwatch.net> wrote:
> I'm familiar with J3M, but unfortunately none of the current J3M/informacam
> techniques actually work, as they have no _external_ verifiability. There
> isn't actually any information which ties the media to a place or a time,
> it's just information encoded into data which could be applied to any
> document at any time. By factoring the network, a geotemporal pkey system
> would address this problem. J3M is good for tying information to a specific
> device (sort of) - but not to a place or a time.
>
> R
>
>
> On Mon, Aug 26, 2013 at 4:58 PM, Lee Azzarello <lee@guardianproject.info>
> wrote:
>>
>> Informacam
>>
>> "InformaCam is a mobile application for Android that enables users to
>> inflate image and video with extra points of data, or metadata. The
>> metadata includes information like the user’s current GPS coordinates,
>> altitude, compass bearing, light meter readings, the signatures of
>> neighboring devices, cell towers, and wifi networks; and serves to
>> shed light on the exact circumstances and contexts under which the
>> digital image was taken. With InformaCam the app starts to behave
>> almost like Adobe Photoshop or GIMP, supporting non-destructive,
>> layer-based edits to media built on top of Obscuracam."
>>
>> https://guardianproject.info/apps/informacam/
>>
>> There is a sub-project to standardize metadata called j3m.
>> http://j3m.info/
>>
>> -lee
>>
>> On Mon, Aug 26, 2013 at 7:08 PM, Rich Jones <rich@openwatch.net> wrote:
>> > This is a small, unfinished idea I had, but I'd be interested in hearing
>> > any
>> > feedback anybody here might have to offer. Normally we talk about
>> > cryptography to secure communications, but this is an idea rather about
>> > verifying the authenticity of media.
>> >
>> > [Quick backround: OpenWatch is a global citizen media network using
>> > mobile
>> > phones as the basis for a free worldwide press. We care very much about
>> > the
>> > authenticity of citizen media, and have designed some systems which
>> > attempt
>> > to improve the verifiability of citizen media.]
>> >
>> > The problem is that sometimes media artifacts are presented as a record
>> > of a
>> > current event, when in fact they from different events. An example of
>> > this
>> > was when images of a marathon race in Istanbul were presented as images
>> > of
>> > the recent Occupy Gezi protests.
>> >
>> > Now, imagine the globe divided into a grid coordinate system, say
>> > 100,000
>> > units (or perhaps 232, if IP rather than physical address is to be
>> > used).
>> > Based on their physical location, reporters can contact a server and are
>> > assigned a key with which to sign or encrypt their media to. This then
>> > ties
>> > a media object to a physical space. This can be further improved to
>> > include
>> > both time and space by dividing a space-day into a number of units,
>> > suppose
>> > 1440, such that different keys would be handed out at different times of
>> > the
>> > day, thus further tying a document to a moment in time as well.
>> >
>> > Does anybody know if any systems like this have ever been discussed or
>> > designed in the past? I suppose this is somewhat similar to the
>> > RSA-keyfob
>> > system, although this allows for anonymous access without
>> > pre-arrangement as
>> > well.
>> >
>> > R
>>
>
>
>
> --
> —————————————
>
> Rich Jones
>
> OpenWatch is a global investigative network using mobile technology to build
> a more transparent world. Download OpenWatch for iOS and for Android!