Question how can I catch exam cheaters that use HDMI splitters to mirror their monitors

[itchycomputer]

Hi,

I think a student of mine is cheating on his exam and I need help to prove it! A little bird told me that a student added an HDMI splitter to the graphics card output and send it to another room to mirror his monitor. So, there is a second person who can see the monitor and signal to the student what the right answer is.
When I asked my student to share his screen, I only can see one monitor in the display setting (because there is only one HDMI connected to the graphics card). I asked him to use his webcam and show me the room, but there are so many cables behind the computer and with low light in the room, it was literally impossible to spot the splitter. I also didn't want to ask him directly to show me the HDMI cable from the case to the monitor because that would suggest I have prior knowledge of his plan.

So here is my question: how I can say that he is splitting the HDMI signal? There should be a way for me to find out, right? There are big online proctor companies and I am sure they have a way to say if someone is clandestinely using an HDMI splitter otherwise everyone would just use this method to cheat.

 

[bill001g]

There has to be hardware to do that but you can't tell with software. There are also monitors that have that feature built in that are designed for say a business conference room.

I mean if someone can install a HDMI splitter and run a cable to another room how hard would it be to put in some kind of hidden camera that could see the screen.

 

[Aeacus]

There is no way to detect 2nd monitor, when external HDMI splitter (or any splitter) is used. Other than visually seeing the splitter.

For other solutions;
Now, i don't know if you can modify the exam, namely questions asked, but if you could, you can add extra question for him alone. So, when results are turned in, his answers should only contain the extra question. And if anyone else's answers contain the extra question, then it's clear that he shared his questions/answers with someone else.

Another option is making deliberate error, where e.g question #5 is same as question #14, but only for him. For all others, questions are all different. So, when results come in and there are more than 1 set of results, which was only meant coming in from him, you could sniff out the copycats.

All-in-all, teachers must outsmart their students, making exams tricky to be copied.

And without knowing more how the answers are given (e.g free form answers, select correct answer from selection of 4 etc), it's difficult for me to give other solutions.

Edit:
Back in my school days, one of my teacher made an exam, which in total, had 60 questions. Teacher split the exam into 3 parts, 20 questions each, per student, and spread them between students. Meaning that only 1/3 of all students in the class had the same questions. While other 2/3 had different questions.
This made the copycat nigh-impossible, especially since buddy of mine had completely different questions.

You could, technically do the same, where e.g if you have 20 students, you make 4 different sets of exams, with different questions. So, you should be getting 4 sets of answers, containing 5 result papers. So, when results come in and e.g set #1 has only 4 result papers, while set #3 has 6 result papers, then you can easily narrow down the copycat.

Ideally, every student should have completely different quesitons, making copycat impossible. <- This is how my final exam was held in my vocational education center, to get my profession papers. We all had different questions, albeit only 3 questions. But those questions were though ones, needing quite a bit of explanation for the answer.

 

[Math Geek]

the second person is not taking a version of the test. sounds like that second person is simply telling the student the right answer from the next room.

think the only thing you can do is to figure out how the answers are being passed on. being in the other room means they have to be sent in somehow. most likely a text or something similar is used. with the student's webcam on, you should see him/her looking to far off screen at the phone. such as on the lap, mounted on the monitor or other way to keep it in view.

but there is no way to tell if he is simply splitting the monitor to another screen.

i taught high school and had similar concerns at times and i could usually get the student in front of me to take the test. parents were more than happy to make it happen when i explained my cheating suspicions. that may be the only thing you can do really.

 

[USAFRet]

"In yesterdays class, what did we discuss?"
Choose one of the following:

 

[ex_bubblehead]

Essay questions for the win. Weight the questions such that the multiple guess questions are only worth 1/4-1/3 of the total score. Cheating there won't help much at all. Otherwise, in person testing is the only way to be sure.

 

[Ralston18]

Maybe you can get the student's computer to tell on itself.....

What screen sharing software are you using?

Are you able to remote into the student's computer?

There are ways but they are dependent on how much actual access is available.

FYI:

https://zditect.com/blog/2600255.html

From the link:

" wmic bios get serialnumber"

Test on a two monitor system to ensure that the command works.

Also:

https://www.groovypost.com/howto/find-advanced-display-information-monitor-windows-10/

While watching the student's screen walk him through a few "quick steps" per the link above.

Ideally if you can remote into the system the reveal should be straightforward.

Also doable via Powershell.

 

[itchycomputer]

Maybe you can get the student's computer to tell on itself.....

What screen sharing software are you using?

Are you able to remote into the student's computer?

There are ways but they are dependent on how much actual access is available.

FYI:

https://zditect.com/blog/2600255.html

From the link:

" wmic bios get serialnumber"

Test on a two monitor system to ensure that the command works.

Also:

https://www.groovypost.com/howto/find-advanced-display-information-monitor-windows-10/

While watching the student's screen walk him through a few "quick steps" per the link above.

Ideally if you can remote into the system the reveal should be straightforward.

Also doable via Powershell.

Thanks! These links are very useful, especially the first one. I simply ask him to share his screen and open the display sitting (along other things). The windows display setting shows that there is one display detected. I can remote to his computer too. I can take control of his mouse and keyboard if I want.
I can test the tips in the first article on my own system first and see for example what serial number is returned if I use a splitter. if it returns two models or serial numbers then that indicates it can detect the mirror monitor.

 

[BFG-9000]

I should point out that HDMI splitters that bypass HDCP do so by emulating a monitor so you would only see the serial number of the splitter and not the attached monitors.

Honestly no splitter is needed since the student could be wearing glasses with a cam in them. This reminds me of mechanical aimbots which only require a low-resolution webcam pointed at the screen and move the mouse physically so no anti-cheat software can detect anything amiss.

 

[itchycomputer]

Hi! I wanted to ask you if you found the solution to this problem, because exams are coming up before summer and I would like to make sure my students don't copy.

it seems there is no way of detecting an HDMI splitter

 

[LinuxDevice]

There might be a way to know via monitor of the EDID data, but to do this is far beyond the average person's knowledge, and requires admin access to the kernel driver. If a splitter is done correctly, then even the EDID probably won't give it away (but this works both ways, even someone with a lot of knowledge might have difficulty customizing EDID).