I filled a survey today which states that it can only be done once a month. If I try to do it again, I am not allowed as expected.
I am trying to find out how they know that it is from the same computer.
So far, here is what I tried :
I used another computer on the same LAN, and I am allowed to fill the survey. So it is not my IP address.
I used the first computer, but with another "private" IP address (192.168.X.X), and I am not allowed to fill the survey again. So it is not the combination of IP address + private IP address.
In Chrome, I cleared everything from the past hour and I still can not fill the survey again. So it is not something they put on my computer.
The only option I can think of is my MAC address, but I am not sure it is an information they have access to and I don't really know how to change it (on Ubuntu).
So I am curious as to how can they uniquely identify my computer as a computer which answered the survey.