Subject: RE: Atom feed design for a variety of media types

From: "Brian Smith" <[email-masked]>
Date: Mon, 14 Jan 2008 19:25:47 -0800

James Abley wrote:
> My initial problem - meta-data
> -------------------------------------------
> I think I can use the Yahoo Media RSS Module for RSS 2.0 [1], which 
> should cover that. Otherwise, I'd need to introduce something similar 
> to that module, which covers the shortfall. Or should I be using RDF 
> or Dublin Core? Any experience or suggestions with this?

Media RSS seems really verbose to be sending to a mobile phone. I think
it makes sense to send the Media RSS-annotated feed to the gateway, have
the gateway choose alternatives based on the phone's capabilities, and
then send a compact, customized feed to the handset.

> Next problem - content expiry
> -------------------------------------------
> Predominantly I think this is required for news agencies, so that they

> have control over what gets displayed downstream.
> My initial ideas, seemingly confirmed by the archives, are for one of 
> the following:
> 
> 1. A separate feed, the semantics of which are understood to indicate 
> content expiry / deletion.
> 2. Tombstones.
> 3. Expiry explicitly indicated on feed items, again with an extension 
> element / attribute, or RDF or Dublin Core.
> 
> I think that the Tombstone discussion is going to go on for a while, 
> and I'm quite comfortable with the idea of the first choice, unless 
> anyone violently disagrees.

If you are in control of all the clients, then I would recommend using
FeedSync. That will allow you to easily support bidirectional (actually
n-way) syncing if/when you need it. Conversely, if you need to support
current Atom clients, then I recommend against FeedSync. I think #1 is
the worst idea because it doubles the number of feeds that the handset
needs to poll. When I was doing stuff with handheld devices, I had to
reduce network traffic as much as possible, because the average user has
a really bad internet connection on his phone.

- Brian