Minimizing cheating in online final exam? What technologies or techniques are practical for minimizing cheating and collaboration in a University final examination that is to be held online? 

I have seen some third-party arrangement which requires the student to keep a webcam operating during the entire duration of the examination, and read here of using a Zoom teleconference to monitor all the students as kind of a remote proctoring. 

As we get into the fall term with COVID-19 restrictions still in place in many countries, this has to be a common concern to ensure the value of the resulting credentials. My immediate question is triggered by a colleague teaching an advanced undergraduate 4th year online course in an engineering discipline, and the student body is pretty international both ethnically and probably (at that time) geographically, so time zone differences may be a factor. Questions are more theoretical than numerical so the MOOC techniques of randomizing are unlikely to be of much value. 

My thought is that some form of remote proctoring (preferably by an as-yet unidentified trusted third party recording the webcams and flagging suspected transgressions) and to force the students into one compromise time period (regardless of their location and time zone) would suffice.
I think online protocring is a terrible idea. It is invasive, discrimatory, and doesn't work. It reveals things about a students living conditions they might reasonably want to remain hidden. It relies on having access to a device with a functioning web cam, and good enought internet for it to work properly. As the end of all that, a webcam can't capture you typing on your phone on your lap anyway. Or having someone stood behind your screen helping you. 

In fact, I don't really like the idea of synchronous remote exams. It is really not fair to ask some students to sit an important, stressful, multi-hour exam in the middle of the night. Not does it really work for students who might share a laptop with another hosuehold member who needs it for their job, or has unreliable internet. 

I think the simple fact of the matter is that it is not possible to prevent cheating while assessment has to be online, other than through the use of one-to-one oral exams and many of the things people are despirately trying just make life harder and less fair for everyone without actaully preventing cheating. 

If your questions are theory based, then surely you can tell if a student is cheating, becuase in order to paraphrase another student sufficiently for you to not pick it up, they would have to understand what they were paraphrasing?