Subject: Discoverability of feeds with differing licences

From: "John Panzer" <[email-masked]>
Date: Tue, 6 Jun 2006 17:43:19 -0700

All,

Some sites offer two versions of feeds; one is a 'headline only' version and the other a 'full' version.  Other than the content, a significant distinction in some cases is the license applied to the data in each feed.  (See http://wiki.creativecommons.org/Syndication.)  For example, the Engadget site offers a headline only feed with (the equivalent of a) by-sa Creative Commons license, while its full text is by-nc-sa, prohibiting copying for commercial use.

Okay, so far so good.  But let's say I'm an ad supported aggregator (commercial use of content). I cannot therefore display the 'full' feed and I'll need to truncate or elide the content.  However, I could display the 'excerpt' feed with no problems.  It would be nice if I could discover the related 'headlines' feed (which I can display with full fidelity) if the user tries to subscribe to the 'full' feed through my ad supported aggregator.  However, right now, there's no automatic way to do that.

A link@rel seems appropriate; I'm thinking of doing this:

<link rel="alternate" type="application/atom+xml" title="Headlines Only" href="..."/>

...and then relying on software to determine that (1) there's another alternative version of the feed that (2) has a different license (requires fetching the feed of course) and (3) perhaps should be offered as an alternative to the user, or used instead of blindly truncating text.

My major question is whether a "headline only" feed is an "alternate" representation, or perhaps an "index" to the full feed, or perhaps a new relation (or two) is needed.

Thoughts?

--
John Panzer
System Architect
http://abstractioneer.org

---

From: "M. David Peterson" <[email-masked]>
Date: Tue, 6 Jun 2006 20:21:02 -0600

Hey John,

This is obviously an important question that also relates to the
GlobalClip/Citation work that I Bruce D'Arcus (Cc'd) and myself are
working on to allow the ability to extract all of the relative
meta-data, including licensing information, as part of a copy/paste
operation [web page > Oo.o, Word, etc...].

Thus far I have been using the documentation on Creative Commons
(http://creativecommons.org/technology/metadata/index_html) that
covers this area quite extensively.

My question: Is there any reason why the RDF method described at the
above link should not be the method promoted as the de facto standard?

I completely understand your reasoning behind looking to find a
solution to correctly propagate and promote a particular method for
content producers in whom use multiple licenses dependent upon various
factors such as those you've mentioned.  While using the rel attribute
seems to be an easy route, I'm not so sure that all of the various
distinctions can be properly handled by a single attribute.  With this
in mind, it *seems* that given the existing RDF route promoted by
CreativeCommons covers all of the necessary pieces to allow for such
things, this would by far be the best route to promote to content
producers.

Thoughts?

On 6/6/06, John Panzer <[email-masked]> wrote:
>
>  All,
>
>  Some sites offer two versions of feeds; one is a 'headline only' version
> and the other a 'full' version.  Other than the content, a significant
> distinction in some cases is the license applied to the data in each feed.
> (See http://wiki.creativecommons.org/Syndication.)  For
> example, the Engadget site offers a headline only feed with (the equivalent
> of a) by-sa Creative Commons license, while its full text is by-nc-sa,
> prohibiting copying for commercial use.
>
>  Okay, so far so good.  But let's say I'm an ad supported aggregator
> (commercial use of content). I cannot therefore display the 'full' feed and
> I'll need to truncate or elide the content.  However, I could display the
> 'excerpt' feed with no problems.  It would be nice if I could discover the
> related 'headlines' feed (which I can display with full fidelity) if the
> user tries to subscribe to the 'full' feed through my ad supported
> aggregator.  However, right now, there's no automatic way to do that.
>
>  ...and then relying on software to determine that (1) there's another
> alternative version of the feed that (2) has a different license (requires
> fetching the feed of course) and (3) perhaps should be offered as an
> alternative to the user, or used instead of blindly truncating text.
>
>  My major question is whether a "headline only" feed is an "alternate"
> representation, or perhaps an "index" to the full feed, or perhaps a new
> relation (or two) is needed.
>
>  Thoughts?
>
>  --
>  John Panzer
>  System Architect

-- 
<M:D/>

M. David Peterson
http://www.xsltblog.com/

---

From: John Panzer <[email-masked]>
Date: Tue, 06 Jun 2006 20:14:51 -0700

Hi David --

Not sure whether you're referring to feed licensing in general, or to 
the problem of feeds with differing licenses and their relationships.  
Can you clarify?

In either case, I think that requiring RDF in order to license a piece 
of content would inhibit uptake.  I think that's why most of the methods 
described at http://wiki.creativecommons.org/Syndication don't embed RDF 
directly.  Of course they are indirectly referencing RDF in the case of 
Creative Commons licenses, so people who have RDF processors can 
certainly apply them constructively.  However the license relations are 
not limited to RDF.

In general, on a discussion, design, and implementation level, trying to 
deal with

<link rel="license" href="http://creativecommons.org/licenses/by/2.5/"/>

is a lot easier to deal with than

<!--

<rdf:RDF xmlns="http://web.resource.org/cc/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<License rdf:about="http://creativecommons.org/licenses/by/2.5/">
<permits rdf:resource="http://web.resource.org/cc/Reproduction"/>
<permits rdf:resource="http://web.resource.org/cc/Distribution"/>
<requires rdf:resource="http://web.resource.org/cc/Notice"/>
<requires rdf:resource="http://web.resource.org/cc/Attribution"/>
<permits rdf:resource="http://web.resource.org/cc/DerivativeWorks"/></License></rdf:RDF>

-->

It's also, of course, much shorter, which becomes important when you 
consider the use of per-entry licenses in synthetic feeds.

The same arguments apply to microformats, I think, which is why 
rel-license exists...  which might be relevant to GlobalClip.

John

M. David Peterson wrote:

>>  <link rel="alternate" type="application/atom+xml" title="Headlines 
>> Only"
>> href="..."/>
>>

---

From: "M. David Peterson" <[email-masked]>
Date: Tue, 6 Jun 2006 21:32:58 -0600

I'm not sure why I didn't realize this before, but as soon as you put
"license" into the rel attribute it clicked for me.

Okay, then I guess the question is not whether the RDF route shouldn't
be promoted, but rather does the rel="[license]" approach allows for
enough implied information to be extracted to be implemented in a way
that allows for contained information to represent a "tag" that points
to the proper RDF information that in turn points to the proper
resource.

The code to make something like this work and work well is SUPER easy,
and off the top of my head I can't think of one reason why
rel="cc:by-sa" shouldn't just work and work well by simply keeping a
local RDF data store, or pointing to a community based data store to
pull out the proper URI information that this particular license then
relates to.

Whats REALLY nice about this approach is the inherent ability to make
a simple change the RDF data and have this propagate across an entire
domain/organization appropriately.  So if CC updates to a new version
of the by-sa license, which obviously can and more than likely will
happen at some point in the future given that the current 2.5 license
suggests that a 1.x and 2.x family is already represented.

Of course there are those who are going to jump in and suggest "Don't
use Qnames in content cuz' of reason a, b, c" do which my response
would be "already have a fix... I've just never published it."

Maybe now would be a good time to publish that fix? :D

-- 
<M:D/>

M. David Peterson
http://www.xsltblog.com/

---

From: "M. David Peterson" <[email-masked]>
Date: Tue, 6 Jun 2006 21:37:38 -0600

Didn't finish out that last thought in the fourth paragraph.

---
... future given that the current 2.5 license
suggests that a 1.x and 2.x family is already represented, + then this
will simply propagate as soon as the RDF data is updated
appropriately.
---

-- 
<M:D/>

M. David Peterson
http://www.xsltblog.com/