Hi, the assistant professors of IIT usually do their PhD from abroad. The hands on experience is actually considered. The whole process varies in various IITs. Few things mention below matter a lot.

1. Quality of your PhD work. It doesn't matter from which institute you get a PhD, the work you have done will be seriously considered. By quality, it means publishing your research work in high profile journals and conferences with good impact factor.

2. Post doc experience- it varies from IIT to IIT. Project funded from dst and other government bodies are really considered.

3. Ability to define your research area. You need to have a clear vision for your research. The practical knowledge matters at last. So the research work and projects are really counted.

Hope this helps.