1st interview is online via skype (15 min max) then the technical interview at the site (1 hour+) and this interview is the core of the job they will ask about every detail in your resume and will make sure you've a background in all the key roles mentioned in the job description, so my advice is to print the job description and highlight the things that you're not familiar with and ask them at the end or within the interview. After that the HR department will contact you for a 3rd interview if you've been selected and finally if you've been accepted they'll contact you and you'll have a meeting with the head of the department.
Good luck!