Based on my three decades of teaching experience, in engineering colleges and IT Industry, PhD in the area of computers and guiding doctoral scholars:
PhD is necessary for taking up a teaching position. If you take admission to PhD now, then you will be joining a college after 3-5 years, as and when you complete your doctorate. If you are well off financially and no family responses , then it is okay. Else you may need to rethink on this decision.
If you have financial constraints, then it would be better to join a college and start teaching. Within a year you can apply for PhD.
Now coming to the burning question which you have posed:
PhD from state universities or deemed universities or private universities?
Discrimination and different pay scales are offered depending on the management decision. This is because many teachers take the remuneration which is offered by the college. In many colleges, the faculty is told to sign on a particular amount while a much lower amount is paid to them. Discrimination also comes in based on the teacher's capability.
You can check the list of UGC approved universities who are permitted to run the PhD program from the UGC website. The list includes all universities across the country.
Also PhD admissions are not easy and the duration is not fixed, it can start from a minimum of three years to may be even eight to ten years. Survey the Universities in your area, prefer state followed by private and deemed universities.
Checkout the following: University website, the admission procedure (GATE score university level entrance exam, interview), admission dates, research areas offered, information about guides and their research area, faculty research publications.
PhD admissions are not easy. The candidate is expected to do some research or extend the Master's work prior to the interview and atleast should be clear about the area.
If you have selected a particular university check out the guides and meet the one whose research area are aligned with yours.
Hope this answers your question.
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