Re: minutes of face to face meeting

Hi JC,

On 15 Jan 2014, at 00:48, JC Verdie <jicheu@yahoo.fr<mailto:jicheu@yahoo.fr>> wrote:

[…] I wanted to say again that I don’t think this group should work on the two UA case, which is already covered elsewhere in the W3C.

Depending on how the group works and where it’s headed, it might be a good thing to communicate with other groups but I’d rather avoid having two places for the same discussion.

Moreover, the one UA case is very specific and leads to various new opportunities and should be handled with care. That’s already a lot on one’s plate AFAIC.

Thanks for explaining your concerns. I agree that we should keep our work in this CG in scope and not try to solve problems which are already handled in other groups.

What Anton and I suggested was one change to decouple primary and secondary screen: moving away from returning a WindowProxy (which enables full DOM access) to instead having a loser coupling, based on a MessagePort.

This helps in various ways: It does make a possible implementation based on independent UAs easier (which would in principle be also possible with WindowProxy, just more complicated), but it also makes a single UA implementation easier: A tight coupling between primary page and secondary page - enabling DOM access - is tricky to handle on the implementation side, especially in browsers that implement a cross-process / renderer-process isolation model.

We do not actually intend to specify whether an implementation is to be based on or two UAs. As also explained in the charter [1], this is considered an implementation detail.

We also do not intend to specify something like a cross-vendor bridge for MessagePort. Wes correctly pointed out that that problem is solved through PeerConnection.

Practically speaking, by having a less tight coupling between the primary page and the second one we give more flexibility to the implementor, and help adoption of the API.

Dominik

[1] https://github.com/webscreens/presentation-api/wiki/Second-Screen-Community-Group-Charter#out-of-scope

Received on Wednesday, 15 January 2014 14:58:03 UTC