I was contacted by a recruiter via LinkedIn in April, and one week later, we had a call. He asked me to talk about myself, and afterward, he explained the process in detail: two screen interviews of 45 minutes each (Networking and Coding), and if I passed those, four virtual/onsite interviews (Technical, Design, Behavioral, and Coding) of 45 minutes each. During our call, he asked me some questions: - What is a tuple? - What is a list? - What is a dictionary? - Name three flags of the TCP header. - Name three fields in the IP header. - Provide a brief description of a ROADM. After that, he sent me all the information for the next steps, and I scheduled my two screen interviews. I chose a date one month later to have time to study. One month later, I completed the two screening interviews. Networking: He asked me: - If we have two devices connected to a switch, and the switch is connected to a router, what protocols and configurations do we need to use to communicate between the devices, such as to connect to a web server? (IP, ARP, TCP) - What is the difference between flow control and congestion control? Could I wait for 10 seconds, for example, in a TCP connection, or is there a limit? (TCP calculates a timeout based on RTT) - Describe one routing protocol in depth. I chose BGP. I talked about attributes, iBGP, eBGP, the number of sessions in iBGP, split horizon, and the basics of route reflectors. Coding: Take the standard input of the vmstat command and print a message if the value of a specified column is higher than the given threshold a certain number of times. vmstat | python my_script.py vmstat | python my_script.py 200 7 2 - Discuss time complexity and space complexity. I didn’t manage to finish this problem because I froze for a few minutes and forgot how to handle the standard input and arguments. However, when I told this to the interviewer, he helped me. My advice is to ask for help at the beginning of the interview if needed. I thought I didn’t pass these steps because of my performance in the coding interview, but one week later, they informed me that I had passed, and I scheduled the last four interviews. I used the same strategy as with the screening, choosing the latest possible date, one month later. One month later, I completed the four interviews. Technical: - If there are two interfaces connected between them in the core network and they are not working, how should I find the problem? (Connecting by console, ping, config, check interface, make a loop to verify the interface). - Discuss BGP in detail, as in the first networking protocol. How to influence the input traffic? I mentioned prepending and MEC, but the interviewer wanted a response about influencing the traffic with announcements of different masks. For example, announcing a /23 to one ISP and a /24 to another. Design: The recruiter asked me to design an access network: - How do you connect the devices? - How do you connect the uplink? - How do you connect the routers? - How would you use VRRP? Behavioral: - What are your motivations? - Why Meta? - Describe a time when you received negative feedback and didn’t agree. - Describe a time when you did something wrong. - Describe a time when you gave negative feedback. - Who is your mentor? - Describe a project that you started on your own. - Management question. Coding: - Write a function to check if a string is a palindrome. - Read text from a file separated by % and print random messages when the function is executed. - Discuss time complexity and space complexity of both tasks.