Sonus Networks Interview Experience

I got an opportunity to have an Interview with Sonus networks, Bangalore. Following is my interview experience:
I got interview opportunity through Elitmus .So the first round was a pH test which consisted of aptitude, English and logical questions .
After the ph test, the interview drive was conducted at Sonus bangalore office.

Around 200 people had appeared for the interview at the office premises

1st round
It was a one-to-one F2F technical interview. Some of the questions were:
1. Difference between list and array in C++.
2. When do you use new operator.
3. Some linux commands.
This round lasted for about 15 mins.

2nd round
This was also another F2F technical round on core java. Some of the questions asked were:
1. Methods of object class
2. Some output related questions
3. Command for compiling and running java code
4. Questions on projects
This round lasted for about 1.5 hours.

3rd round
Round started with interviewer asking me questions on what all areas I am comfortable in Java.
Then he started asking questions on using data structures in java.
Asked me question on multithreading. (write the code to start 2 threads and print the thread names).
Another question was to given a circular linked list, how would you traverse it if you are not given pointer to the head node.
I was rejected after this round. However it was a very great interview experience with Sonus Networks.