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nagkumar

Joined: 05/Feb/2008 00:00:00
Messages: 5
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Hi,

I begin to understand D2D idea of ICEfaces and have the following things bothering me .. Any experts pl. advice

My understanding..
1. As D2D makes browser a dumb terminal and server having the full context of what is at browser.
2. This way server could know what is the icremental dom w.r.t to latest output dom and send only the increments for dumb terminal to update.

Few scalablity issues:

In the server to know the current context, it either has to keep what was served to each user or should request the dumb terminal to send their current page along with latest request info.

In the first case impl of server keeping the copy of dom at server, would mean more memory and hence would this approach scale up for commertial deployments like yahoo.com,youtube kind of heavy load sites!

In second model, the memory consumed is less compared to first approach as we are requesting from the browser on demand and releasing it onc the request is serverd. However, this would consume more network upload bandwidth. Though this may taking less bandwidth than entire page update without ajax model, still this could be concern for mass adoption, where upload bandwidth on dialup is quite less.

Could any one advice, what model icefaces is following of the two above and how scalable was icefaces in any real deployments, pointers to figures would help us.

Regards,
Raja Nagendra Kumar,
C.T.O
www.tejasoft.com


ted.goddard

Joined: 26/Oct/2004 00:00:00
Messages: 874
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ICEfaces maintains a DOM on the server, hence uses slightly more server memory and significantly less network bandwidth than standard web applications.

We're in the process of measuring the scalability properties of ICEfaces, but it's important to keep in mind that it is a "stateful" technology (as is JSF, and generally JSP). Stateful technologies provide enhanced features for the user, but require server-side resources to do so.
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nagkumar

Joined: 05/Feb/2008 00:00:00
Messages: 5
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Hi,

Thank you for the details.

How does server side DOM gets updated on server, in case the user has javascript call which does few modifications to browser DOM.

Regards,
Raja Nagendra Kumar,
C.T.O
www.tejasoft.com
ted.goddard

Joined: 26/Oct/2004 00:00:00
Messages: 874
Offline


If JavaScript is used to modify the DOM client-side, care should be taken that the modified region is not updated by the server.

No mechanism is provided for propagating DOM updates back to the server for several reasons: determining these updates in the browser would be time consuming, network resources would be consumed relaying them back to the server, and finally, changes to the DOM have no natural representation in the JSF component tree because components produce markup as output.

(An interesting exception to this is the rich text editor component, because the model of this component is a DOM that is edited by the user.)

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