three rounds of interview. HR first contact me first with some basic questions (where am I currently working at, what's the expected base salary, etc. as well as two basic technical question). Then I received the call from the team manager two days later. Been asked some basic network, operating system and C++ questions. About 3-4 days later I had the onsite interview. There were 4 rounds. each 45 minutes with 2 interviewer. Still basic questions about data structure, algorithm, TCP programming, security....