It was an employee referral.

I had four rounds:

• Telephonic
• Technical
• Technical Manager
• HR

The process started with a telephonic round, focusing on C++ questions such as virtual destructors, constructors, and virtual functions.

The next day, I was called for a face-to-face interview. This round focused more on Linux kernel internals, and I was asked to write a program to implement the Singleton pattern.

After a week, I received a call for the Technical Manager round. This interview covered network security and networking fundamentals.

Finally, I had the HR round.

Be prepared for standard C++ questions, delving a bit deeper but not overwhelmingly tough.

Ensure you are comfortable with networking basics, C, C++, and data structures.