[xorlof]

Lots to reply to. What a great "problem" to have!

Originally Posted by Cinisajoy

...most if not all should know how to use a power bank.

Yes, pretty much everyone probably knows how to use a powerbank. The goal of this to have a very polished, pro-level player (and tournament director) aid available. Plugging and unplugging power banks is hacky. I like hacks (this whole project would be a kind of hack), but I don't want to have to depend on that sort of hack if possible. The whole point of this exercise is to bring our "professionalism" in running the event to the next level.

If that response doesn't feel satisfactory, feel free to expand this spoiler for a rambiling explanation of an important (to us) detail. All but the people most dedicated to understanding our reasons are advised to skip the spoiler:

Spoiler:

I guess that one thing I haven't explained is that for this sort of event to feel like it's been run super smoothly (remember, that's one of the goals in adding these devices), there are a critical few minutes during the changeover from one round to next. Given these two things:
1) We want every round to launch on time at (for example) the top of the hour.
2) Every round has games that do not complete in the allotted time (and a winner is determined via some alternate rules).

When time is called, we already have the results for games that didn't go long. That's great. But at that point the players who were still playing have to do a pretty quick calculation to determine who wins their game, record those results, and relay them back to the tournament director's table. Until ALL results are in, the tournament director usually can't really do too much in starting to determine the next round's pairings.

However, we are a very friendly community, and after you finish a game, espeically one that was fought to the bitter end, what normally happens is that time is called, the players figure out who won and then start chatting about the game...perhaps how tense or close it was, or disappointments, or whatever. (And sometimes the players themselves try to sneak in some extra play). Getting the results to the tournament director (TD) quickly is far from their mind. Remember the TD *needs* those results before they can go to work. What usually happens is that the TD ends us going table-to-table on the games that went long (sometimes after figuring out where the players actually were playing) trying to collect results. For various reasons, this takes some time (several minutes) at events that are the size ours are. At that point, finally, the TD can determine next round pairings and only then can they be announced so the next round can start. (End of rounds are a busy time for the TD also because this is when players are most likely to have miscellaneous questions for the TD).

So what does this have to do with the Kindle? The speaker on the Kindle I'm proposing using can audibly prompt (or even nag) players to report their results when their game goes long. I think this will short-circuit the delay that exists in games getting called on time and players sending results back. Secondly, the results get transmitted electronically which can saves time physically moving them around (currently done with small slips of paper). All of this saves time and frees up the TD during this time to take care of other stuff, rather than trying to get results from players.

Results being electronically entered also means that after the last result is submitted the server can instantly calculate the next round pairings and immediately display them on every kindle (with a beep on all of them to signal to everyone to look at them). You pick up the nearest kindle (all of which at this moment are automatically displaying all of this round's pairings), note which map you have to go to for your next round, set the kindle down, walk to your spot and start playing. This saves time too. It gets the pairings out very quickly. Our current "state of the art" is to post a printout of all of the rounds' pairings that players crowd around until they can get close enough to see their name and map number.

All of these time savings (with getting results, calculating pairings, and distributing next round pairings to players) means that there is more time to actually play the games. Currently, if our 1:00pm round is finishing (next round is supposed to start at 2pm), and there are lots of games threatening to go long and the event is large, we may have to call time at 1:50. That gives the TD 10 minutes to 1) go around and hassle players for results, 2) determine next pairings and 3) distribute/post them. Sometimes that 10 minutes isn't enough and the schedule slips which exacerbates our time problems for the next round. If players get used to responding the kindle's prompting and immediately enter results, we might be able to call time at 1:58 or 1:59 for a 2:00 launch of next round. Combine that with all players being seated at the start of that 1:00 round by (say) 1:02 instead of 1:05 means that overall players have 56-57 minutes to play their games instead of 45, a difference of 11-12 minutes. About 25% more time to play! THAT'S HUGE and it means fewer games will get called on time and more reach a natural conclusion which makes everyone happier.

How does this tie in to your question? At the crucial switchover times between rounds, if the TD is busy dealing with technology (e.g., someone forgot to plug in a device to a battery bank so it's dead and you can't report results, what's that router password again?, etc.) it *kills* the schedule. Most of the time, minutes don't matter. At the beginning and end of rounds, it does, and this is precisely the time when people are mostly likely to have a kindle in their hands, needing it to work. If it doesn't and someone can't report results (i.e., a dead battery to directly address your question) that's a problem, and a problem at one table makes 60 other players wait. Don't get me wrong; our players are patient and understanding, but making them NOT have to wait is part of the job of a tournament director. We need something simple to use (from the players' perspective) and super-duper, no-questions-need-to-be-asked, no-problems-need-to-be-addressed reliable.

Trust me, that is important to us.

All of that said, previous posts about protecting the Kindle from damage and frequent references to power banks have made me think it wouldn't be too hacky to use a kindle protective rubbery case from ebay (~$3) and slide one of these thin usb battery banks ($2.50 from ebay) INSIDE the case, taped inside to the kindle, and have the battery bank ALWAYS plugged in. Here is a picture of the cheap battery:



It would make the rubbery case bulge a bit up top, but I think it would look OK since it would all be one sleek unit (no plugging and unplugging of the batter and it doubles the watt-hours available). I'm ordering a sample case and battery to test it, just in case it turns out my battery life test comes up short.

Regarding the later part of your post (why not just use tablets or smartphones and such), see my response later in this post.

Originally Posted by Yourcat

With one SoHo router you may get connection issues unless you connect only a few clients. SSL requires CPU and SoHo routers often don't have enough. Running a load test over LAN with an increasing number of clients fetching a dynamic page every 60s should reveal the router limits.

That's a good consideration. The router I'm using has a (IIRC) dual core ~1ghz arm processor. Reasonably beefy. TLS/SSL is not required for us. (If we wanted privacy, everyone would already have essentially a private channel talking to the private router if we had WPA turned on. Remember traffic does not leave the router to go to a seperate server). The server architecture envisioned is such that there is heavy caching of anything dynamic. Leaving the details out, it means the server is really only recalculating anything on average once every minute and a half or so, with a peak of probably 8 data submissions/recalcs in one minute (at end of round). Results are cached after each recalc. The only expensive operation is the player pairing calculation which only happens once an hour. I think I can safely say without testing (and understanding that I write lean code), that it will be able to handle it. What do you think?

Originally Posted by Barty

xorlof: I think you're going to have to bite the bullet and write a test app. Something that polls the server and downloads something, does some busy work to simulate processing, and displays something.

Yeah it looks like it. I've been playing around with the Kindle after I jailbroke it Thursday night which means I haven't done the test yet, but will do so in the next few days. Running the test itself takes a half a day (if all goes well and the battery holds out)!

Originally Posted by Barty

Any reason you want to avoid going the smart phone/tablet route? Do you have a no phone policy at the tournament? Your users look young and geeky, and it should be little problem to have them bring their own device. You can supply them with portable chargers and/or outlets as a courtesy. You just need to write the web app.

A fair enough question and one I've been dancing around until this post. There are lots of reasons, most of which I will try to restrain myself from going into too much detail with (as you can tell from my previous posts--I *love* detail!):

1) It would be very useful to have always-on display assigned to each map. It's always there. Always showing what's needed. It provides map and pairing-specific information INSTANTLY--no hunting for the right URL--just glance over at it. It can also function as an always visible game timer and player alert system, always controllable by the tournament director. A hodge podge of tablets turning on and off can't do any of this, nor can player provided smartphones. It's ubiquitous availability itself is a killer feature.

2) We do NOT have a "no phones policy." People do have and use their phones between games. I think most players would frown upon the use of phones during games (except for specific circumstances). We generally like to be quite interactive with the player in front of us. It's a great aspect of our culture. The tournament asking players to use their phones during games for official tournament purposes could start us on a slippery slope (including players using phones as aids to calculate tactical game information, which I suppose then could lead to a ban).

3) If you read the spoiler above, you'll see (in excruciating detail) that if this system works, the Kindles should provide us a lot of time savings per round, and you'll also read about the benefits of that. The time savings is actually is probably the #1 benefit to us.

4) We need whatever electronic system we use to be battery operated. The Kindles' (hopefully long) battery life gives it a huge advantage for us over tablets. Getting electricity from various venues (think at large gaming conventions) is expensive. We usually pay for one power drop to power a laptop at the tournament director's table (and it would also power the router/server located at that table in this proposed system), but the venues do not look kindly on stringing extension cables around to other tables. The reason for not using a bunch of battery banks is covered in the spoiler, but briefly, we need reliability. There are certain times we can't afford to encounter a dead battery even for a couple of minutes. (That's also why the idea mentioned above of essentially a permanently attached external USB battery *would* be acceptable.)

5) As mentioned quite a while back in the thread (easy to overlook), I can get these Kindles DIRT CHEAP. $10 each dirt cheap. With good battery life remaining. That saves a LOT of money, since we're talking about a lot of stations. Not sure if we could afford this otherwise (remember, just volunteers setting this stuff up for free).

6) While you didn't mention a "bring your own device"-only policy I want to address that here before someone does. Not all of our players have their own devices so we couldn't require that. The game is accessible to pretty young kids (8 year olds or even younger) and they sometimes enter the tournaments. Because there is a lot of strategy and tactics involved, young kids like that won't win, but they still have fun and most of the older players sporting enough to restrain themselves from absolutely trouncing them.

7) Any amount of bringing your own devices can mean more problems to troubleshoot. This isn't a big deal, but I mention it as a downside. Over time 99% of these wrinkles could get ironed out.

Originally Posted by Sukarn

I'm not OP. I believe the main idea was that having a device that is always showing current or recent info without needing a button press would be a nice addition for them.

Yes. I know I'm not the best communicator, and apologize for that. I think you understand me very well though so at least I can say I'm not a total failure at communicating my intentions!

For those keeping track, expect my battery testing results later this week. For funsies (not related to this project), I'm also building a lego minstorms ebook "reading" (actually just page turning) robot to test how long the batteries in these devices REALLY last when reading books (not using manufacturer numbers). Anybody know if someone else on the forum has already done this? I have my Kindle 3, a Kindle Touch, and a Nook Simple Touch that I will be testing. (The results of this testing will have its own thread). If there is enough interest I might try procuring some other (more recent) devices for testing purposes.

Thanks again for your help everyone. It's nice to see that some others find this to be a cool/fun/interesting/whatever idea. And I would have never hit on the "always attached" external battery INSIDE of a rubber case idea if not for this bouncing of ideas off each other. Whether I need that or not right now, it will come in handy as the kindle batteries start failing if easy, cheap replacements are no longer available!