It was an exhaustive process. 5 rounds. All the rounds were equally detailed against my expectations. I was expecting subsequent rounds to become tougher but it didn't happen. Round-1: Panel had 2 people (Sr.Engineer/Lead I guess) Interview consisted of basic C questions like: - Write a prototype for String concat function - Implement the above prototype. There were cross questions like what should be the return type (status code SUCCESS/FAIL) Input string should be const* or not. Should the input also contain a length field to take care of non-NULL terminated strings? Who will take care of malloc/free (caller or the implementation). What things u'll have to take care if u make this function compile as a library - re-entrancy etc. - Second question was related to link list operations. It was a puzzle popularly known as the link list Y problem. You can google for it. Questions were raised on complexity of the algo and the best solution possible. I was not asked to write any code for this. - Implementation of Binary tree - implementation of circular linked list and then writing a program to add a new node at the end and delete the existing last one. - 8 queen problem on a chess board - priority inversion - what are priority queues - write a program to generate combinations of a given set of characters - use of volatile type qualifier - how does windows socket communication work in single server multiple client and single thred system - difference between semaphore and mutex - count number of 1 in a int - how to multiply a number by 7 without using multipilcation and and addition - how is negative number represented in C - how to detect loop in linked list - how to delete current node in the linked list when previous node is not known - how to find middle of the linked list - AVL trees - strcmp function ( optimized implementation, hint: using checksum ) - 8 ball given find the odd ball in 3 tries (odd ball can be heavy or light ) - OS implemetation of mutex and semaphore - - Then they asked a puzzle..which was quite easy to crack..They also asked me to ask them a puzzle :) and I did that. Overall the round was very open...interviewers were very friendly and I never felt any stress. Round-2: 1 guy. Senior Manager. Asked me in detail about my current project. --He was interested more on the network side of IMS. , So I went into the details of CSCFs. --He specifically grilled me a lot on how an IP packet is routed in IMS network (UE to PCSCF--ICSCF--SCSCF)...and was finally convinced. But was a very friendly guy and kept me at ease. Round-3: 1 guy. Senior Manager. Very cool and friendly guy. Tried to understand how routing in IMS works ? Then asked me IP related questions. How IP routing works ? Subnetting ? How Ping works ? DNS, ICMP, ARP, DHCP, etc ? Round-4: 1 guy. Senior Manager. Asked me if I had written a "sufficiently big" C program in previous round ? Made me implement a binary tree. Source code went up to 4-5 white sheets. Asked few cross questions on the code and corrected me where he felt I was wrong. Round-5: 1 guy. Senior Manager. Asked me to explain how all layers of protocol stack work and which network entities are involved - starting from the moment you type a URL in web browser till the time the page is displayed. Then asked me lot of non-technical questions like "what makes a good manager"? What are good qualities of a team player ? How do u think u'll manage work life balance here under high work load etc etc... Basically he wanted to study my temperament..as there are no definite answers to these questions :)