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Re: Internet at Competitions
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That is not how the RF Spectrum works. You can't just throw more power at it to solve all the issues. There is a finite amount of bandwidth that can be squeezed into each frequency range. Throw in interference from multiple devices that may or may not play nicely with each other and you are in for a mess. On top of that, general purpose equipment will NEVER be faster than specialized equipment (like the Cisco routers) even if the general processor is an order of magnitude faster. There are good reason why quality equipment costs a lot of money. |
Re: Internet at Competitions
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Re: Internet at Competitions
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For example: You could get Zebra for Unix as a Cisco-like router built from a PC. or You could get a real Cisco router. Now...for around $2,000 you could get a Cisco router suitable for a T1 PRI interface to the Internet (about 1.544Mbps) with the module containing the CSU/DSU. A PC with all the parts to make this work is not a much better deal. There is a strange point however: let's say you have cheap high bandwidth to use like say 150Mbps to the Internet (a real 150Mbps say on an OC3 fiber circuit). Keep in mind 'cheap' in this definition is thousands (in some cases tens of thousands of dollars) a month. The suitable Cisco equipment to harness that might be quite expensive. However this is cheap transit. You don't really care so much that it's 99.99% up. You just want to use it. So you slap some PCs on it with PCI Express cards and you accept that the performance might be touch and go for the major savings in price. Back to FIRST: FIRST is not really in the business of being an ISP or phone company. They need it to work in a way that qualified (but volunteer) folks can handle it and not be so unusual that it becomes dependent on a single person. If FIRST needs hardware for say wired Internet they are dividing what is likely between 1Mbps and 40Mbps link between 20-100 teams. Used - but quality - gear from Cisco is available for cheap that can handle 10Mbps ports to the teams with a nice uplink speed back to the a single higher speed switch. Put the slower switches out near the teams in the pits. Run the uplinks from the various pit areas to a the higher speed switch. Then put whatever traffic control system that can be afforded at that point with either a router or...if the venue has it already...just plug it into the venue network. Even if someone uses a PC as long as it can be supported (say Untangle or something like that) to rate limit and filter the result would be adequate - but still the Cisco hardware when it comes to hardening will outperform. It's possible with Untangle to pump 200k connections and several hundred megabit of traffic. Rate limiting (using tagged packets and VLANs) says you share what you have and it is unlikely you'll get a huge Internet connection with the field and streaming going on anyway. That is more than enough for a scouting application. In point of fact: many businesses might be thrilled to have even that. Keep in mind: it's better FIRST put that Cisco gear for that is purpose in the field than Untangle. You loose your scouting app that stinks. You loose your field because a single power supply failed and that is bad. |
Re: Internet at Competitions
1306 sets up a network for scouting; this allows us to backup our data offsite as well as being essential for CrowdScout so that other teams can get data updates.
We tether a phone with an (unlimited) data connection over Bluetooth to Computer A. Computer A is set to share this internet connection from the Bluetooth PAN to Ethernet, which is fed to a router (with WiFi disabled). The router shares it among our network, which is entirely Ethernet. (Ethernet allows us to expand the network by using switches if needed.) Sharing files on our local network can get complicated because we run across Windows, Linux, and OS X. Generally we set up a SMB/SMB2 share hosted off of Computer A if we need to exchange many files. The system is very scalable and incredibly reliable - only one wireless link is used, so there's rarely issues with interference (as compared with a Bluetooth many-device network). We're looking at getting rid of that link, too, using a USB OTG cable and USB-to-Ethernet adapter. |
Re: Internet at Competitions
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I do not believe that FIRST extends that rule to 3G/4G. If they intend it that way, then I should hope it is limited as a rule applying to the team. In other words: if 3G/4G data service is not allowed it is within respect to team efforts (like scouting applications). I say this because: I have global planetary responsibilities (in short this is no joke and it could impact everyone, everywhere). Frankly if there is service I need to be available. I can cooperate only so far with this. I can check in occasionally. I can and do take the day off while at a competition. However I can not allow FIRST to create a situation that could lead to a level of harm they can't possibly have liability insurance adequate for. 3G/4G to a phone client does not present a risk to the field. Turning on a WiFi hot spot on your phone might. Frankly I think any interpretation of that rule to prevent 3G/4G client access for people that are in situations such as myself will literally cripple FIRST (consider the corporate sponsorship: the number of FIRST mentors, volunteers, organizers and parents that are in situations like myself). The only way that makes sense with regard to 3G/4G is to cut down on teams with team efforts to use the Internet. In short teams should not write Internet applications but individuals data usage on 3G/4G as clients only on that network is okay. Besides this would be entirely unenforceable. The number of smartphones by nonaligned spectators directly next to the field with active network synchronization on 3G/4G would be large. FIRST would have to tell every spectator to turn off their phones and even then there would be people that would not comply. Start weeding them out and quickly it will hurt FIRST's reputation. At the point that FIRST as an organization goes >that far< stop playing around with WiFi for critical field functions because it is manufacturing many problems where there need not be any. Going >that far< actually has a tangible cost in reputation and likely support. So whatever it ends up costing FIRST if they had to make that leap balance that against the potentially much higher risk of financial impact. Do not interpret this is a threat. Interpret it as what it is. I am an engineer this is my observation of the risk. |
Re: Internet at Competitions
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Instead of sending things through the internet, write the info down on paper and give them to someone who can put it in a computer! It's not too hard to do that! I had my scouting setup like this (although we never really used it because we didn't do too well this year): 1.Everyone goes on their phone and submits a google form with all the parameters. 2.Google Spreadsheets automatically gets the data 3.Google Spreadsheets sorts the data and averages everything and makes graphs 4.The scouter (or the drivers) pulls up the interface (a sheet with a spot to type in the team you want) and gives us the info on the other teams Now I could make it where people just write down the info on paper and have one person compile it into a sheet in excel or the new google offline spreadsheets and it will do the same thing Besides, what's the point of robotics if you are going to be on the internet all day? It is actually fun to watch! (unless it's your team, then it's nerve wrecking):yikes: |
Re: Internet at Competitions
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Re: Internet at Competitions
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Re: Internet at Competitions
In this case, I did want to put data on a site, available to everyone. Having just limited internet access can help teams with less members, teams that need scouting help, etc. Using an online service allows you to use a powerful service. If I ever get my scouting app done, at the end of the match, the team can push a button for the server to process the data, build graphs and do a side-by-side comparison between different teams, and sort through teams. The software would allow you to sort through teams so that, if you are in a big competition with many high-scoring robots, the software will help you get what you need in a few minutes, a much shorter time than paper-and-pencil is! That is one advantage of internet-based CrowdScouting (as team 1306 is working on). Also, this will allow one to write a program to automatically fetch the scouting data to a tablet in the pits, meaning that a student won't have to walk all the way to the stands to get data!
Even something like google drive's spreadsheets can do the same thing (though since I am not a spreadsheet hero, I think it would be hard to make a nifty interface) |
Re: Internet at Competitions
I'll admit I didn't have time to read every single reply so this was probably said before but...setting up a WiFi network can and will interfere with field-robot communitcations, but I also see the use of having access to wireless communications (notice I say "wireless communications" NOT "WiFi") in the pit/stands. Bluetooth is a perfectly good option, also, a small server/file sharing system, with a router running at a distinctly different frequently from ALL field communications could work, but Bluetooth seems to be the better option by far as to not creating interference. I am not aware of any FRC rules pertaining to Bluetooth use but I have not read the entire rule book.
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Re: Internet at Competitions
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Re: Internet at Competitions
Slightly off topic; when using bluetooth for scouting, how much of a problem is interference from other bluetooth devices? We're pumping some money and time into a bluetooth based scouting system this year, and I'll be sad if we find out that it won't connect through the various wireless noise.
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