Navigating business after academia: Q&A with Software program Engineering Supervisor Hyojeong Kim
Academics work on Facebook at various stages in their careers. Some join as soon as they graduate; others join as professors after long and established careers. Somewhere in between is Hyojeong Kim, who came to Facebook after some time in the industry.
Kim is the Network Routing Software Engineering Manager at Facebook. It owns routing protocols (BGP and Open / R) and associated software services that run on Facebook’s production network, which consists of the data center, backbone and edge networks. Her team focuses on solving routing challenges to support next generation production networks while ensuring production reliability.
We reached out to Kim to find out more about her academic background, her previous Facebook journey, and her recent projects on the networking team. She also advises PhD students who want to take a similar path.
Q: Before you come to Facebook, tell us about your academic experience.
Hyojeong Kim: During my Bachelor’s career in South Korea in the late 1990s, I saw the Internet connecting people all over the world. This inspired me to study the core technologies that make the internet possible and contribute to it. That’s why I came to the United States and took part in the Computer Science PhD program at Purdue University.
During my time at Purdue I had the opportunity to learn more about Border Gateway Protocol (BGP) internet routing and its problems. I created a BGP simulation test stand on the internet over a distributed Linux cluster. I was very excited to learn so many new things. When trying to experiment with the latest measurement-based Internet topologies, I encountered many challenges with distributed systems because of the volume of input, and I spent a lot of time and effort creating software tools to aid in distributed simulation.
These were interesting problems in themselves, but they were also very challenging. As a PhD student, I didn’t have the context of how my work could be applied to real-world problems. However, what I learned from my doctoral studies proved very useful in solving real world problems in a variety of ways throughout my career. It has helped me expand BGP to support a quick response to denial of service attacks distributed over the internet, build a Facebook user readiness enhancement system for user traffic, and a network routing software stack for Build and run Facebook data centers. In retrospect, all of my insights and experiences during my doctorate were very valuable. I just had no perspective back then.
Q: What brought you to Facebook?
HK: I started my career at Cisco working on BGP routing software that runs on core routers used by ISPs. I was proud to help found the Internet. After gaining some industry experience as I pondered the next chapter in my career, I had the opportunity to attend the Grace Hopper conference. I was so inspired to meet so many women at different stages in their careers and receive advice from them on how to help women make successful careers in technology. I also met engineers from Facebook and heard about their experiences. It finally got me to join Facebook.
Q: How has your journey with Facebook been so far?
HK: I first came to Facebook as a software developer. Visiting Facebook made it possible to pursue big research questions and be creative, which I was very excited about. I learned how Facebook’s production network connects to the internet and had the exciting opportunity to create and run a software defined network controller called Edge Fabric. This was a research collaboration with a PhD student and his advisors. We made significant improvements to the system and shared our operational experience with the academic community at SIGCOMM 2017.
In the Facebook networking team, we examine our own production network, identify problems, create solutions, make them available for production and continue iterating on solutions, receiving signals from the company. I really enjoyed the opportunity to own the full cycle of problem solving. On Facebook, engineers can be innovative and design their solutions boldly and creatively. This encouraged me to face great challenges.
Within Facebook, it is common and highly recommended to switch teams or try out different job roles. This keeps the work exciting and challenging and ensures that we always learn new things. As a software developer, I have had the opportunity to lead a team of engineers on some important initiatives. Then I became interested in how to grow other engineers and how to support a team in solving several challenging projects. Eventually I became a software engineering manager and now lead a team of software engineers in the field of network routing.
Q: What are some of your latest projects?
HK: I changed my focus to routing data center networks a few years ago. That was the time when the team scaled Facebook’s internal network switch and software stack, FBOSS. The aim was to convert the data center network to FBOSS. During this time I learned and improved the BGP based routing design for data centers. I led the building of a scalable, powerful BGP software and its test / deployment pipeline. These allow us to treat BGP like any other software component and thus enable fast incremental updates.
Using what I have learned over the years, I co-authored the NSDI 2021 paper, “Running BGP in Data Centers on a Large Scale”. BGP was designed for the Internet, but large web companies often use it in data centers. This document describes how we create, test, deploy, and use BGP in Facebook’s data centers, something that has never been thoroughly discussed in science. This paper was a collaboration with our former PhD students Anubhavnidhi Abhashkumar and Kausik Subramanian from the University of Wisconsin and their advisor Aditya Akella. They helped capture our operational experience from an academic perspective.
Q: What advice would you give to current PhD students considering transitioning into industry?
HK: If you are a PhD student who has a similar experience to mine and you are unsure of how your current work would affect problems in practice, I recommend looking for internship opportunities in the industry that you interested If you only have academic experience it is difficult to know how research is applied in industry without actually having industry experience. Internships can help you contextualize your research and give you a fresh perspective that will help you think about how to solve practical problems. In addition, you make connections that may lead to future research collaborations. Internships also allow you to learn about different company cultures and explore what can help you find the right job after graduation.
I also recommend doctoral students attend as many networking events as possible. Attending Grace Hopper was a pivotal moment in my career and it opened my eyes to all the places I could work.
Q: Where can people find out more about what the Facebook networking team is up to?
HK: The networking team’s page is where you can find all the latest publications, news, programs and vacancies. We are also starting an RFP at NSDI ’21. Sign up here to receive email notifications of new RFPs.