I went through a total of three technical interview rounds followed by two management-level discussions. The technical rounds included in-depth questions on VOIP, SIP protocols, Linux system administration, Python scripting, troubleshooting scenarios, and several other related topics that tested both my problem-solving and practical implementation skills
Interview questions [1]
Question 1
Explain how SIP handles NAT traversal. What role do STUN, TURN, and ICE play in this process?
In SIP, what is the difference between a re-INVITE and UPDATE message?
How does SIP forking work, and how is call state maintained across multiple endpoints?
Can you explain RTP vs SRTP? How is encryption managed in real-time media streams?
What mechanisms can be used in SIP to prevent toll fraud?
How would you troubleshoot one-way audio issues in a SIP call flow?
Explain SIP REGISTER, INVITE, and BYE message flows with detailed headersExplain how Python’s Global Interpreter Lock (GIL) affects multi-threaded applications.
What’s the difference between synchronous, asynchronous, and multiprocessing in Python?
How would you parse and analyze SIP packets using Python?
Can you explain Python decorators and give a real-world use case in VOIP automation?
What’s the difference between deep copy and shallow copy in Python objects?
How would you design a Python script to monitor SIP call quality using RTP statistics (jitter, latency, packet loss)?
How do you optimize Python code for low latency in real-time communication systems?
