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RE: Adaption

From: Rotan Hanrahan <Rotan.Hanrahan@MobileAware.com>
Date: Thu, 8 Jul 2004 16:07:53 +0100
Message-ID: <D9BC812593BC2E44A803E6765FFA5E2D657CDF@gpo.mobileaware.com>
To: "Kai Hendry" <hendry@cs.helsinki.fi>, <www-di@w3.org>

Not so safely, actually. The doc reviewed much of what is done today, within the scope of the exercise. A lot of adaptation takes place somewhere between the origin and the client, but the view of the DIWG is that the adaptation could take place anywhere along this path. There may be reasons to avoid one end or the other, so the middle tends to be a "safe" place for now.

Consider an example: CSS-MQ can select styles on the basis of some device properties, and sometimes these properties can only be known for sure at the client. But in a mobile situation, you'd have to send everything to the client so that it could execute its selection process. Not very efficient use of bandwidth, and possibly putting a burden on the client CPU and memory. So the alternative is to get the client to send the essential data toward the server side, to avoid comms overheads, and possibly move the processing to a place where there is more CPU, memory and power.

The picture represents a technique, but you are free to blur the boundaries. In fact, we hope to blur the boundaries quite a lot.

It doesn't propose techniques. It explains techniques that are known, though the techniques are at varying levels of maturity as you will discover when you go "shopping" for an implementation. Pick the one that suits your needs and your budget. (Budget includes your time, not just your money.)

Finally, I can safely say that the general concensus of the group is to avoid too many authoring overheads by using as close to single authoring as is practical while employing adaptation at whatever stage in the delivery is most likely to give the best result. There are no perfect solutions (yet), but at least we'll know one when we see it! (Or hear it, or touch it, or taste it, according to your adaptation mechanism...)

---Rotan

PS: Nokia UA: A summary of the actual issues observed by you w.r.t. this UA might be of particular interest to the audience of this list. And if you care to expand on other UAs it might make for a very interesting report. Similar compliance reports have been done for PC browsers (mostly markup/css related).

-----Original Message-----
From: Kai Hendry [mailto:hendry@cs.helsinki.fi]
Sent: 08 July 2004 15:47
To: www-di@w3.org
Subject: Adaption



After peeking at Authoring Techniques for Device Independence[1], can I
safely say the policy of this WG is to adapt content (ignoring style)
for the device via an intermediate proxy?

As demonstrated in the figure:
http://www.w3.org/TR/di-atdi/intermediate-adapt.png

Or was that "just a technique" proposed?
Like summarisation is just another technique?

If this document proposes a bunch of techniques, as a web developer am I
free to choose any of these? Or is there another guide telling me which
solution I should aim for?


I discovered my series 40 Nokia UA (which is shipping a fair few every
second) does not seem to implement a compliant XML parser, i.e. it
handles everything like tag soup. Who should be worried here? ;)

[1] http://www.w3.org/TR/di-atdi/
Received on Thursday, 8 July 2004 11:07:55 GMT

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