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#211
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Re: [FRC Blog] Einstein Report Released
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Also, in answer to Greg McKaskle's earlier post about some robots DITW with a flashing RSL not being the result of FCA: Here's a likely example. GTRWest (ON2)'s Finals match 2, 1114 dies partway through, with a flashing RSL. It was a Wk5 event. The vulnerability existed then. Probably one of the non-FCA reasons. The first shot of them dead on camera is when the match clock reads 87 seconds remaining. Immediately before this shot, the red alliance station is shown, their red light lit solid. Match clock 54, the red alliance station is shown again, solid light. Based on my understanding of the failure mode of FCA, a solid alliance wall light is proof of something else being at fault. At match clock 51 of Einstein SF2.2, 2056's alliance wall light is seen flashing. Knowing how the FCA bug operates, its easy to see how it could be caused accidentally, and I wonder just what percentage of the post-Wk4 comms issues could be attributed to it, even if the person operating the failed client didn't intend or even realize the consequences of their actions (or the automatic actions of their Wifi devices). |
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#212
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Re: [FRC Blog] Einstein Report Released
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#213
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Re: [FRC Blog] Einstein Report Released
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#214
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Re: [FRC Blog] Einstein Report Released
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Is it actually the color of the bumpers? Will putting red bumpers on a robot make it fail, or will blue bumpers fix it? Of course not. What about the wifi? It turns out that all traffic is sent out on the same wifi frequency and channel. Red and Blue robot traffic is literally chopped into small packets and transmitted one after the other in a big data stream. RF spectral noise cannot bias red or blue or any particular robot. Additional APs using the same channel will not bias based on color or robot. The data is sent out over the same antennae. The AP has six antennae, but three are tuned for 2.4 GHz and three for 5 GHz. The three antennae are used in MIMO fashion to modulate the bits of each packet. No bias there. The packets are the same size, and only difference is that the control packets have either an ASCII R or B within an inner field. B is 0x42, R is 0x52. The adjacent field has an ASCII 1, 2, or 3 for the alliance station by the way. Team ID is used as the SSID name. This resolves to a unique BSSID which is one of the six MAC address of the router. The MAC is in the IP packet header and nothing about team number, color, or anything else is. No opportunity for bias that I see. That leaves us with the physical cables that deliver the data from the DS to the wifi AP and the switches that merge and route them. I don't have an explanation for how they would bias. Finally, the report gives details as to root cause. I don't see failures following colors or stations. I mostly see things following robots. Please explain the mechanism or let this one die. It is a small sample size and robots in elims do not swap bumpers. Quote:
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2. Well if it is true for FaceBook, ... Greg McKaskle |
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#215
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Re: [FRC Blog] Einstein Report Released
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I hope that hailstorm doesn't come to them. To what you did say, of course they will be mad, and justified in being so. Last edited by Ekcrbe : 15-07-2012 at 00:38. |
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#216
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#217
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Re: [FRC Blog] Einstein Report Released
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And does anyone else think it might be beneficial(or in some ways detrimental) to have two topics of discussion for this ne political, one technical. Or would that just draw too much attention to the political stuff/become a battleground?Last edited by Steven Donow : 15-07-2012 at 01:12. Reason: Android chief Delphi is not kind |
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#218
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Re: [FRC Blog] Einstein Report Released
I challenge the FIRST community to be above this and avoid putting this stigma on an unfortunate team and consider everyone in this team's influence innocent until proven guilty. There's no guarantee the perpetrator acted alone, but it would be even sadder and stranger to find a cast of co-conspirators. I doubt this will be the case.
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#219
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Re: [FRC Blog] Einstein Report Released
Did anyone from 1717 get to formally investigate with FIRST the cause of their issues during division eliminations?
Seems logical to look into their case as well as other communication issues during eliminations at Champs, albeit, probably without inviting all teams to Manchester it might be difficult. At least it would give these other teams piece of mind as well knowing that it is not solely some issue with code/electronics that caused their issues during elims. Last edited by Akash Rastogi : 15-07-2012 at 01:55. |
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#220
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Re: [FRC Blog] Einstein Report Released
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Suppose the perpetrator leaves the team because of graduation? The "individual" was not identified in the FIRST Einstein Investigation Report as being a mentor nor student. Wouldn't the FIRST community would be more forgiving if this was more like a teenage "stunt" rather than an attack on sportsmanship and GP by a team leader? If a mentor did this, the team involved likely would suffer irreparable damage to their reputation. Last edited by David Brinza : 15-07-2012 at 06:31. Reason: Grammar |
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#221
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Re: [FRC Blog] Einstein Report Released
Good work on FIRST and all volunteers and afflicted team's parts with their swift and thorough analysis.
Good work on catching the issues with smart dashboard. Good work on 118's part in identifying their own issue with their gyro reset loop. Good work on 118's and volunteers parts again for working to identify the issue with their vxworks network buffer being overrun following the cessation of normal crio code activity. Good work on all parts reminding us that its probably best that our cRios never run at 100% utilization, and that its perfectly plausible to not hit 100% doing all sorts of complicated logic, whether you're running c++, java, or labview. Good work on deciding to limit team bandwidth moving into the future, our applications are only going to get greedier with time and we need to have a cap. Good work spotting all wiring problems that were in fact present with several of the playoff teams. And good work and god speed in all future efforts in securing the field against any external interference, be it intentional or not. The only secure network is one that's disconnected, but we can all (and I'm sure will all) do our best to improve the quality of experience for all FIRST teams. |
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#222
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I don't think so either. |
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#223
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Re: [FRC Blog] Einstein Report Released
Everyone,
It is my firm belief that the individual involved acted alone, without the knowledge of the team. In fact the team was cooperative in the investigation. A witch hunt to determine the team involved serves no purpose. Further I do not believe the person involved in the attack did so to target a specific team and prevent them from winning. The choice of which team to attack seemed merely a means to an end to prove that a robot was vulnerable. The sentence for the individual as spelled out in Jon's letter was harsh but just, as it should be. Should someone else, student or mentor, discover an issue in the future that compromises the competition, I hope that this sentence will dissuade them from demonstrating the issue during match play. I hold no ill will against this team and will gladly play with them in the future. In my opinion the mentors demonstrated GP once they were aware of the issue. I doubt students on the team were aware of the situation at the time. Any further action will only serve to harm the team, the students they serve, and the community as a whole. I wish them well in the future. |
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#224
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#225
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Re: [FRC Blog] Einstein Report Released
There is one more thing I wish to share which was a symptom 100% reproducible where during the switch from autonomous to teleop showed no connection and we continued to have lost connection until near the end of the match.
This happened at our first match last year... Unfortunately I do not know the full reason as to why, but it had to do with how much work was done cleaning up objects that ran in autonomous and starting similar ones up again in teleop. The good news is that we could reproduce this problem using the practice button (So yes there is good reason to test with it). We had to disable autonomous for that competition to avoid this symptom. I should add using the practice button is a great test, but it could give a false positive. It may be that the instantiation (or cleanup) is just on the threshold and with any more network time delay could throw it over the edge. I just want to throw a word of caution to all programmers to not make the same mistake we did. Be aware of how much work occurs between ending autonomous and starting teleop(). We never found the root cause of this, so I do not know if the vulnerability still exists. What I can tell you is that we instantiate everything on powerup, and do the minimal amount of work to transition from autonomous to teleop. In regards to the current subject at hand... I just want to add this as a diagnostic check if a similar symptom occurs or had occurred. |
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