The basic differences between MR at IIT Madras and Ph.D. at IIT Madras are

• Research: MS program has less research work than Ph.D. It is considered an extended version of MS and many MS students go for a Ph.D. afterward.
• Degree: An MS degree is awarded if the student has a minimum of 1 international conference paper and if the panel is satisfied that the work has met the standards of the institute. Whereas a Ph.D. is awarded only when the student has a minimum of 2 international journal papers and if the panel is satisfied and considers it as per the standards of the institute.
• Coursework: An MS student needs to take at least 5 graduate courses whereas a Ph.D. needs to take 4. Additionally a Direct Ph.D. or M.S.+PhD. needs to take 8.
• Duration: The time taken to complete an MS program is between 1.5-3 years whereas for a Ph.D. and M.S. + Ph.D it takes 3-5 years. This duration might be increased in case a student is unable to complete it in the given time frame.
• Viva: In Ph.D., you are required to pass a challenging Viva Voce, while in M.S. you need not. The difficulty level of this viva varies from department to department.
• Stipend: Under the HTRA scheme, an MS student gets INR 12400 while a Ph.D. student gets INR 25000.

Despite these differences, the general routine and schedule of both MS and Ph.D. are similar. Ultimately, more than your program, your research topic and performance will matter.