This was my first interview after a gap of about 7 years, and I was pleasantly surprised. The entire process was pretty smooth and took about three weeks. I had an initial round of phone screening where I was asked to code some string/tree manipulation problem on coderpad. I was then called onsite to their SF office where I met with 6 engineers. Had a variety of domain related questions related to SSL, cryptography, AES , ipsec, hashing etc. A couple of interviewers asked me coding questions about reducing overlapping intervals and system design questions. The hiring manager spoke to me at the end and answered all questions I had about the team, product and company.