He also addressed the letter to the chairman of the IIT-B board of governors.
The unnamed professor expressed anguish at this trend and urged measures to correct the situation.
There has been no official comment from IIT-B yet.
IIT-B a victim of rampant cheating
Students employ a variety of cheating techniques
The letter claims teachers have often found students hiding notes in toilets, then retrieving them on the pretext of using lavatories during exams. Many have been caught using mobile phones during exams; sometimes, "impostors have appeared in the examination halls to help out their friends".
Academic pressure taking a toll?
Surveys by student magazine InSight have displayed a tendency to cheat: in 2014, every second final-year undergraduate student admitted to cheating at some point, and in 2015, 20% respondents said they would happily cheat if given a chance.
InSight also found that compared to studying six hours a day before clearing the JEE, study hours came down to just 1.4 after getting admitted.
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The dean who legally allowed cheat-sheets
Former Dean of Student Affairs at IIT-B, Professor Urjit Yagnik, said, "I allow students to carry a cheat-sheet to exam, and tune my questions to concepts rather than memory. This reduces anxiety in students and allows me to test what really needs to be tested."
UP CM Adityanath's "anti-romeo" concept lends a hand
Meanwhile, the professor, in his letter, has proposed measures to check mass cheating; one of them suggests setting up anti-cheating squads "along the lines of anti-Romeo squads employed by Adityanath in UP".
The institute has installed CCTVs to keep a check on such incidents; it also has a strict punishment policy in these matters, ranging from losing a credit point to failing the student.