- From: Håkon Wium Lie <howcome@opera.com>
- Date: Mon, 29 Nov 2004 15:58:46 +0100
- To: public-webarch-comments@w3.org
- Cc: www-tag@w3.org
Also sprach Chris Lilley: > The comment about reduced size resulting from server-based processing > was not, however, referring to this aspect at all. Instead, it was > referring to the work of the DI working group, whose CC/PP framework for > server side content adaptation allows, among other things, images and > video to be tailored for the device. If the original content references > an image that is 800 pixels wide, and the phone screen is 200 pixels > wide, then sending the original image rather than a downsampled one > merely makes the download 16 times larger for no benefit. Ok. Yes. That wasn't clear in the original draft. > I understand > that Opera has a server based product that does these sorts of > transformations.[2] Indeed. > To resolve this ambiguity and more clearly describe the tradeoffs for > the two extremes of the spectrum, the following revised text is > suggested. Please let us know what you think of it. it will be discussed > in the next couple of days at the TAG f2f. Good. Your revised proposal is close to where it should be. I have the following comments: > Note that when content, presentation, and interaction are separated by > design, agents need to recombine them. There is a recombination > spectrum, with "client does all" at one end and "server does all" at > the other. (I'd add "end of the spectrum" (or just "end") to the end of the above paragraph to make it easier to read.) > There are advantages to each: sending device capabilities to the server > (for example, using CC/PP) allows tailoring of the content to specific > devices (such as mobile phones). For example links can be adjusted to > point to lower resolution images, smaller video or no video at all, > giving a faster download; if the content has been authored with > multiple branches, the server can remove unused branches too. In > addition a small amount of client side computation is saved. However, > this makes the content more specific to a particular device, reducing > caching efficiency. > > On the other hand, recombination on the client makes the delivered > content applicable to a wider range of devices, improving caching > efficiency. How about: On the other hand, recombination on the client makes the delivered content applicable to a wider range of devices. This improves caching efficiency and gives users more presentation options. > It can be tailored to particular groups of devices by > using media specific style sheets. For textual content with a regular > and repeating structure, the combined size of the text content plus > the stylesheet is typically less than that of a fully recombined "stylesheet" -> "style sheet" > content; the savings improve further if the stylesheet is reused by > other pages. ditto. > In practice a combination of both approaches is often used, tailored > to the particular content. -h&kon Håkon Wium Lie CTO °þe®ª howcome@opera.com http://people.opera.com/howcome
Received on Monday, 29 November 2004 14:59:26 UTC