Received a phone call from a recruiter talking about the position. Then had a phone interview for tech screening with one of their programmer team, asked some fundamental questions about network protocols, big O notation and some basic programming questions. Got the notice for an on-site interview the same day. One week later, had the onsite interview at their Reston headquarter, interview lasted about 4 hours with 6 people in a 6 rounds 1 on 1 interview. Each lasted 30 min. The interview went pretty smooth, had most of the questions prepared and answered. Had not received any feedback after the interview, thought I got rejected in a silent way. I don't think that is professional.