Concept - Web Based Information Display Network With Synchronized Video Playback

All,

I've been brainstorming a network of web based displays and need to know if a few things are possible in modern web browsers without addins / etc.

Concept - We have a large facility with several thousand employees. I am working to introduce a network of web based displays (probably 400 to 500 when all said and done) throughout the facility. These would be a cheap display (probably a TV so we have integrated sound as opposed to a monitor) and a chromebox or similar small chrome based device that is hard coded to boot directly into a browser and to a specific URL for that display (probably through the query string, ?DisplayID=123 kind of thing). The web server hosting all of this would be local on site so bandwidth isn't much of a concern.

Most of the time these displays would show performance data, and work area specific information. However, in non-work hours, we could turn these into a digital slide show with information etc that employees would want to know. This should all be very simple to do.

Here is the (potentially) tricky part. I think it would be super cool to push a video to all of the browsers and have them stay in playback sync. For example, we could share a training video, or recognition video, and easily reach this huge audience without having to gather everyone in a single place. The sync part would be important, as many of these displays are going to be within 10 to 20 feet of each other, so if not in sync, would just be a mess from an audio standpoint. Even cooler would be the ability to push a live stream to the screens for special events or to give our leaders an opportunity to speak to the larger population. All of this should be able to be managed from the server side without interaction on the displays (they will all be on a async refresh cycle, so thoughts would be that from server side we tell the web app to display video div and play video from x url at y time and then use some type of sync event to keep them all aligned?)

So my question is around the video piece. I'm a decent web developer, but have not developed much in regards to video or streaming. Doing some googling brings me to HTML5's video tag and some inherent features there. I guess my specific questions are this:

1. Is this idea possible within standard browser capabilities (without add ins or 3rd party software)?
2. If so, what would be the basic components? I'm not really looking for sample code or anything... just a general idea of how to approach the solution.

Thanks!

John