Interview Cisco Sytems SDET

Cisco Systems Interview Experience : SDET, Pune, India

One fine day...i got a call from Cisco HR if i was availaible for an interview with Cisco Systems for an SDET position(call was correspoding to my refferal made by one of my friends there)in the coming week..? I agreed. Following is the narrative of my interview experience with Cisco.

First was a telephonic screening round. They were two guys and they started with my project i made in college. They asked me to write small pseudo code snippets of what i did and seeked some explanation for it. Then they said the interview would be split into two halves - networking and programming. In networking they started with the explanation of Basic OSI networking model and slowly started to go deeper and deeper.Some of the more specific questions involved explaining some protocols and examples where they are used like ARP,DHCP,BGP,OSPF etc. They were more interested to know which reference layer they work at. Then there was some discussion on multicasting , IPV6 addresses , MAC address. 

First half went quite good and they started with the programming section. It started with questions like difference between the main () function of c and c++...i told them of the return types...they were not fully convinced though. Then they wanted me to write a linked list reversal program and dictate the code. They asked me how comfortable i was in OOPS... i told not much but the still continued with the standard OOPS questions. They grilled on virtual functions and their use. It was more of a theoretical interview where they were checking if a am aware of basic Computer science fundamentals. They also touched upon the basic Unix commands and wanted me to explain what happens when commands like 'ls' is typed on a shell.

This round lasted for a bit more than an hour and i thought i had done more than OK in this screen.

After a wait of 3 days i finally got a call from Cisco HR informing me that the inerview went OK but they want to have one more telephone screening round, this time with the Technical lead. I agreed for the next day afternoon interview. This time there was only one lady...who was a technical lead of the team i was interviewing for. This interview was purely programming based. She asked me some questions on linked lists..how to delete a node with only its pointer given. I knew this question before hand and skillfully gave its answer...considering  i was only 10 months out of college she seemed impressed:) She wanted me to write a program to convert a decimal number into binary and trust me i fumbled at this question ... She moved ahead with the discussion on complexities of algorithms...she wanted me to explain The Big O,theta notations and seeked some examples of sorting algorithms and wanted to know their complexities. Then she asked if i know of any scripting languages like Perl Python ...my answer was a NO but i told given the time i can always learn them with a good programming knowledge.

                                This round lasted for about 50 minutes and then i started a wait for a long time of 10 days before I finally got a call from HR that if i could come for an inHouse interview. I agreed and and had my first flight of the life for an interview in Cisco campus. This time the interviewers were 2 people from the team..One manager and the same team-lead who took my second phone screen. They started with the heapsort question and wanted to know the applications where minHeap can be used as a datastructructure. Second question consisted of finding the middle element of the linked list...i told we can maintain two pointers (fast and slow) , fast is incremented by two positions and slow by one and when fast reaches end then the slowere pointer will point to the middle position. They were quite satisfied with the explanation and wanted me to code it. And guess what the third question was..?WAP to convert decimal to binary....the exact same question i fumbled upon in the second screen...they are  interested to see if a person does some homework after the interview..thankfully i did and was able to answer that..and i could see a smile on the face of the TL:P

This round lasted for about 50 minutes and then I had lunch with the TL...

                                As a final round i had to face the Business unit head...and to my surprise it happened to be a Technical too...He asked me questions on multiCast Addresses. Wanted to know the difference between static and global variable and wanted me to to explain the process structure in memory.Followed with the normal discussion on why Cisco and if i was ready to relocate? Interview ended well and then i was asked that I am done for the day and HR will contact me.

I got a call a week later confirming my selection.

Things to lookout for a Cisco interview:

1) networking:- OSI model,specific protocols and their applications (IP,TCP,BGP,OSPF,ARP,RARP),addressing techniques (classfull and classless,v6,multicast,broadcast addresses).

2)Programming:-Basic Linked list,trees problems , basic searching sorting algorithms(merge quick heap among standard ones)...they wll not grill much especially for freshers,1-1.5 years.

3)Operating system: A decent knowledge of Unix and basic OS fundamentals-threads locks memory process management.

luck
-House