I had two rounds of telephonic interview and 2 rounds of face-to-face and then HR interview. I was asked everything related to Telecom Domain that i had mentioned in my resume. I had applied for Senior Software Engineer with SIP protocol background and i was asked questions on consultation transfer/ Proxies/ Registrar Servers / NAT /TURN/ STUN etc.. All questions were posed such that unless you have working experience on these, you cannot answer those questions with just theoretical knowledge. Answering to such questions which makes you think and recollect what all you have worked on, was fun.