Rotational Network Engineer Program Overview

Network Engineer Role at Meta

  • Implement solutions quickly while considering long-term infrastructure needs (e.g., 5-year plans).
  • Account for space, power, and cooling in data centers (DCs).
  • Adapt to constantly evolving technologies to ensure secure and reliable network capacity.

Data Center Fabric

  • Interconnected switches and routers that support network traffic.
  • Designed to be modular for easy management and maintenance via software.

Backbone Network

  • Interconnects data centers and points of presence (POPs) globally.
  • Treated differently from the DC network.
  • Meta operates one of the largest scale DC and backbone networks in the world.

Rotational Network Engineer (RNE) Program Overview

  • Ensuring network reliability, robustness, and scalability to serve over a billion users.
  • Developing and deploying network designs, automation systems, and performance improvements.
  • Scale is tremendous; automation and continuous improvement are crucial to meet demands.

Network Organization at Meta

  • Networking Infrastructure:
    • Network Core Services
    • Platform Engineering
    • Data and Networking
    • Network Planning
    • Traffic and Edge
    • Network Security
    • Network Investments (requires longer experience, less relevant for RNEs)
  • Diverse objectives across teams.
  • RNE program exposes engineers to most of these areas.

RNE Program Details

  • Full-time, paid position with the same expectations as full-time employees.
  • Four to six-month rotations to explore different areas of network engineering.
  • Mentorship is provided for career guidance and navigation.

RNE Onboarding and Rotation Process

  • Three-week boot camp for all new engineers.
  • Work with various teams on tasks and projects during rotations.
  • Soft team matching to identify areas of interest.
  • Final rotation project (RNE graduation project).
  • Full team matching after graduation.

RNE Team Options

  • Backbone Engineering
  • DBE
  • Network Core Service (NCS)
  • Data Center Network Engineering
  • Network Security
  • Traffic and Edge
  • And more

RNE Eligibility

  • For early-career individuals and recent graduates.
  • Also suitable for those with a few years of industry experience.

RNE vs. Direct Team Match

  • If a candidate has specific network expertise and matches a team directly, the RNE program may not be necessary.
  • RNE is not an interview process but a working opportunity to explore teams.

Networking Interview Process

  • 1-on-1 video conference interviews (45 minutes each).

Networking Fundamentals Interview

  • Focus on:
    • ARP
    • DNS
    • DHCP
    • NAT
    • IPv4/IPv6
    • TCP
    • BGP and other basic routing protocols
  • Opportunity to ask questions.
Networking Fundamentals Tips
  • Ask clarifying questions.
  • Verbalize assumptions before providing a solution to allow the interviewer to follow along.
  • Be prepared to explain in detail.
  • Review interview preparation materials.

Network Design Interview

  • Focus on designing networks or systems to operate at scale.
  • Designing network elements or systems with reliability, scale, and efficiency in mind.
  • Opportunity to ask questions.
Network Design Tips
  • Clarify goals and requirements of the system.
  • Only ask questions that might affect the design.
  • Describe the system at a high level and explain the overall architecture.
  • Draw diagrams that clearly describe relationships among different components.
  • Prioritize a working solution, focus on scalability.
  • Identify trade-offs in the design and describe how decisions were made.
  • Calculate back-of-the-envelope resource estimates.
  • Adjust the design based on changing requirements or constraints.
  • Determine how the system will perform at scale and identify bottlenecks.
  • Familiarize yourself with the xCairo virtual whiteboard tool.

Coding Interview

  • 1-on-1 video conference (45 minutes).
  • Assess problem-solving skills and limits of knowledge.
  • Repeat the question to ensure understanding.
  • Ask about edge cases.
  • Think out loud while coding.
  • Run test cases through the code.

Coding Environment

  • CodaPad: A whiteboard tool without autocomplete or execution.
  • The goal is to understand the problem, express thoughts, and test the solution manually.

Coding Example: Facebook Logo Stickers

  • Problem: Facebook logo stickers cost 22. Cut out letters to make other words/phrases.
  • Input: String of word(s) made from letters in "facebook" (lowercase).
  • Output: Integer representing the number of stickers needed.
  • Example: "coffee kebab" requires 3 stickers (c, o, three f, k, two b, a).
  • Example: "book" requires 1 sticker.
  • Example: "facebookbook" requires 2 stickers.
Coding Solution Outline
  1. Create a function get_letter_count(word) to map character occurrences in a word.
    • Example: `getlettercount(