Some questions on the legality of Wifi
 

I've heard that Wifi isn't permitted at competitions, but I'm somewhat unsure as to the exact limitations of it.

I want to put a hotspot in our pit at competition this year so that pit scouting can be done on mobile devices and uploaded to a central server. Then, ideally, we can do some statistical analysis to look at our best matches.

I was wondering if 5ghz APs are allowed in the pit area? If not, are there any other IP-over-RF encapsulation methods that are compatible with most mobile devices and tablets?

I do realize that we could upload data over cellular, but it wouldn't work very well for us this year because we're traveling to Canada and roaming data is expensive.

Re: Some questions on the legality of Wifi
 

we've got the same issue when we go to worlds in the US.

I'm considering using bluetooth, but the range goes down a lot

Re: Some questions on the legality of Wifi
 

Let's start with T4. Anything in violation of that will most certainly be shut down by field staff. So your hotspot and your 5GHz AP are both non-starters.


Bluetooth may be an option, but it's rather short-range.

Re: Some questions on the legality of Wifi
 

As a programmer, working with bluetooth is really hard compared to hosting something like a webserver. That's why I wasn't too interested in it...

I've looked into options to have a wired connection to the device, but most tablet-compatible ethernet connections are pretty bulky. The other option is to buy some kind of alternate RF module and then write a custom stack to handle comms, but that would be way more work than we need this season.

Re: Some questions on the legality of Wifi
 

The field uses 5g. Any use of that spectrum in the pits will be frowned upon.

Re: Some questions on the legality of Wifi
 

In conjunction to what everyone else on this thread has said in regards to the violations. Your best bet, at the regional or even before, speak with the Head Regional Director or the field guys to see if they have a spectrum you may borrow while at the competition whether its at a certain time or not.

Re: Some questions on the legality of Wifi
 

The FTA is the person to speak with. With all the pressures of keeping the event on schedule, he (she) is the one running around with his head on fire. Safe bet his answer will be no. Aside from not having the time, how can he fairly give one team access, in violation of games rules, without opening it up for other teams?

Re: Some questions on the legality of Wifi
 

Frank speaks the truth. T4 is very clear. Don't set it up at the venue. Plan for something else.

Re: Some questions on the legality of Wifi
 

Our team has been using a scouting app for the past 3 years, and we have tried many different ideas for data transfer. We have stuck to the tethered transfer, so that we don't break any rules, and it's a quick transfer for a lot of data.

Re: Some questions on the legality of Wifi
 

I saw this during CES: http://cassianetworks.myshopify.com/...c51803009fe0b5

It could be a very good solution since it can handle up to 22 devices and a 1000ft radius.

If any teams end up using it, they should post their results here or somewhere. I'm really curious about this product.

Re: Some questions on the legality of Wifi
 

T4 is completely unambiguous.

Don't set up access points. It doesn't matter if in your opinion you think it won't mess with the field. It doesn't matter if you really, really want one for scouting to work. The rule says, and means, don't set up access points in the venue. The pit is in the venue.

Re: Some questions on the legality of Wifi
 

Even though you'd still be dealing with the issues of range, you could create a Bluetooth PAN network between your tablets for sync up. Bluetooth PAN gives each device an IP address that you could use to run a web server on. To solve the distance issue, have your pit scouters take down data and save it locally to their tablet/phone/device (via the app YOU make), then have them meet with the head scout (during lunch or a match break) and connect to the head tablet/computer via Bluetooth PAN. From there, use your app to sync the stored data and send it to the web server in whatever fashion you like.

EDIT: If you plan on using all Android tablets, make sure they are running 4.0 or later, and do the following for each:

On the PAN host: Enable bluetooth tethering in the settings (If the host is a tablet, you may not find this feature. Try an app like BlueVPN if you're setting it up on a tablet.)
On each device: Pair with the host and enable "Internet access" in the bluetooth device's tab. (This will allow LAN communications between devices).

Credit to ce4 on StackExchange for the answer.

If you so choose, you can also use this method to share Web access from the PAN host (if it is a cell phone) to your PAN devices.

Re: Some questions on the legality of Wifi
 

It was pointed out to me that the FTA and anybody else for that matter does not have the authority to allow teams to violate the rules. T4 is pretty clear. The answer will not be T4 does not apply to you.

Re: Some questions on the legality of Wifi
 

There is a time to think outside the box. Then there is a time to think inside the box.

Re: Some questions on the legality of Wifi
 

Could you use a Farady cage instead?

Re: Some questions on the legality of Wifi
 

Perhaps a Faraday cage can be place over the robots from the teams who keep insisting on setting up a WiFi network each year.

Re: Some questions on the legality of Wifi
 

If other teams can find workarounds for not having wifi you can too! You just need to be...
CREATIVE!

P.S I've always wanted to do that...

Re: Some questions on the legality of Wifi
 

Not if you use T-Mobile.
It doesn't cost me anything extra to use my T-Mobile data plan in Toronto.

Re: Some questions on the legality of Wifi
 

Yep thats the word I was looking for. I agree they will more then likely say no of course.

Re: Some questions on the legality of Wifi
 

FrankJ knows what's up!

In my years working with field setup and the FTA's on Thursday and Wednesday night, we will often have a end of night wifi hunt, where we track down the rogue wifi hotspots in the pits and shut them down. ::rtm::

Re: Some questions on the legality of Wifi
 

We just wrap the robot radio in aluminum foil. It's a lot easier.

Re: Some questions on the legality of Wifi
 

Maybe alicen can do what MrRoboSteve is suggesting. That will put an end to it pretty quickly. :D

Re: Some questions on the legality of Wifi
 

So you go war driving for rogue access points prior to Stronghold?
This is very militaristic :D

I really still think it would benefit FIRST to put someone in charge of getting Internet to the events rather than have people doing all sorts of strange things to get an advantage.

Hey I have a silly question - would FIRST have an issue if a venue hosting a district event offered wired Internet in the pits?

Re: Some questions on the legality of Wifi
 

2959 did get permission to setup a venue wide hotspot last year (hopefully this year as well). To do that though we had a lot of restrictions and we had a network engineer manning it to make sure the signals didn't interfere with each other. So you might get permission provided you can bring $20,000 worth of equipment and a certified network engineer. :)

And even then the equipment was overwhelmed and was only so so. If we get the opportunity again this year we are bringing more antennas.

Re: Some questions on the legality of Wifi
 

It would be difficult working around 4.13 Site Restrictions, bullet 5.

Do not arrange for Internet access or phone lines from venue service providers or attempt to use venue internet connections reserved for event purposes (e.g., FMS or streaming).

Re: Some questions on the legality of Wifi
 

Look at that a different way - it restricts the teams from arranging for Internet access or phone lines. It does not restrict the -venue- from providing said Internet.

Also it wouldn't be WiFi. It would wired. So all one needs is a box of CAT5 and enough switches/switch ports assuming the venue provides an Internet connection.

I am pretty sure I am a tad over-qualified to install a campus wired network ;)
If not there are a few: colleges, ISP and financial institutions around here that wouldn't be working.

Re: Some questions on the legality of Wifi
 

Our programmers are currently looking at periodically using NFC to sync data between our tablets and a master tablet. The master tablet would then have a Roam Mobility plan to get the data back to the cloud:

https://www.roammobility.com/

Re: Some questions on the legality of Wifi
 

I looked into it further, but I am still left with questions. Can you control the smart home devices via their native apps, and if so, does it allow for data transfer to a computer using OBEX FTP? Does it allow for a PAN/LAN like setup so they can access a FTP server on my laptop? I know it isn't released yet, but if someone can point me in the right direction, thanks.

Re: Some questions on the legality of Wifi
 

As a note to those of you considering Bluetooth, keep in mind that Bluetooth operates in the same 2.4GHz frequency range as traditional WiFi. While potentially harder for field staff to detect (as a WiFi scanner will not see it), if it is detected you will likely be told to stop using it.

I came across an interesting paper that describes, amongst other things, how WiFi and Bluetooth interact with each other: http://www.hp.com/rnd/library/pdf/Wi...oexistance.pdf

Re: Some questions on the legality of Wifi
 

The FRC field is not 2.4GHz it is 5GHz.
Of this I can be pretty sure as I have been a CSA/FTAA.

However feel free to take FIRST's word on it:
http://www.firstinspires.org/sites/d...-frc-qanda.pdf
See Q301.

Keep in mind the field security monitoring tools can still detect the 2.4GHz spectrum but usually we don't police it.

When there were issues in the past with the interference the source that caused the most public examples were all interacting with the 5GHz spectrum. Airport radar can also interfere with the top few channels of that 5GHz spectrum.

Also this 802.11n supports channel bonding which is usually turned on but occasionally has been turned off in the past.
So that means that your robots can use 2 channels of that spectrum to get extra radio bandwidth.
That still does not remove the 7Mb limit imposed between your robot and the field.
That bandwidth restriction is imposed not at the radio level but at the protocol level.

Re: Some questions on the legality of Wifi
 

Those (United States) channels are:

• 52 (5260 MHz)
• 56 (5280 MHz)
• 60 (5300 MHz)
• 64 (5320 MHz)
• 100 (5500 MHz)
• 104 (5520 MHz)
• 108 (5540 MHz)
• 112 (5560 MHz)
• 116 (5580 MHz)
• 120 (5600 MHz)
• 124 (5620 MHz)
• 128 (5640 MHz)
• 132 (5660 MHz)
• 136 (5680 MHz)
• 140 (5700 MHz)

It's something that is set by the access point. You can set your client to be able to use 40Mhz channels but if the AP doesn't have 40Mhz channels enabled, you won't get any benefit.

Finally, 80Mhz channels are possible with the 802.11ac Wave 2 access points which can give you an association speed of almost 3.5Gbps.

Re: Some questions on the legality of Wifi
 

You guys should take a look at SuperScouter. It allows data transfer over QR codes (and customizable data forms). Take a look at http://jkoritzinsky.github.io/SuperScouter4FRC