Network Security Engineer

At Cloudflare, we are on a mission to help build a better Internet. Today the company runs one of the world’s largest networks that powers millions of websites and other Internet properties for customers ranging from individual bloggers to SMBs to Fortune 500 companies. Cloudflare protects and accelerates any Intern...

At Cloudflare, we’re not looking for people who wait for a polished roadmap; we’re looking for the builders who see the cracks in the Internet that everyone else has simply learned to live with. We value candidates who have the instinct to spot a "normalized" problem and the AI-native curiosity to create a solution ...

Available Location: Singapore or Tokyo, Japan

Do you love solving complex technical issues and interacting with people? Are you passionate about providing premium-level support to customers and are a standout colleague? Cloudflare is seeking an experienced Network Security Engineer to join our team and support our largest and most technically sophisticated customers in resolving technical problems, threats or attacks on their infrastructure at OSI Layers 3, 4, and 7. This will span the range of Cloudflare products from Magic Transit Infrastructure Protection, Argo Smart Routing, DDoS mitigation and Network Firewall, to using the Web Application firewall (WAF), Spectrum and Rate Limiting to help customers.
Serve as a trusted technical advisor for our enterprise customers, responding to and resolving inquiries and incidents related to network security and performance, while delivering timely, high-quality and personalized assistance.
Work directly with customers to diagnose, troubleshoot and resolve complex technical issues involving DDoS mitigation, firewall rules, SSL/TLS, network confirmation, and other security configurations.
Create and maintain knowledge base articles, technical guides, and troubleshooting documentation for internal and customer use.
Compare traffic signatures and attributes including IP addresses, cookie variations, HTTP headers, and JavaScript footprints to determine what is good traffic and what is malicious
DDoS mitigation for OSI layers 3,4, & 7: advise customers on how to filter malicious traffic using Cloudflare tools like Magic Transit, Network Firewall, WAF, IP reputation lists, packet inspection, blocklisting, allowlisting, and rate limiting
Work with Engineering and Product teams to improve products and tools
Utilize generative AI and automation tools to streamline log analysis, accelerate root-cause analysis during security incidents, and optimize customer response times.

You have a minimum of 4 years experience working as a Network Security Engineer / Technical Support Engineer / Sr. Support Engineer supporting networking or web security products.
Exceptional troubleshooting and problem-solving skills, with the ability to simplify complex concepts for customers.
Strong customer service orientation and communication skills
Ability to work independently and collaboratively in a fast-paced, dynamic environment.
Strong understanding of network protocols, including TCP/IP, DNS, HTTP/S, and BGP, with a particular focus on anycast routing concepts and implementation, as well as tools such as iptables and looking glass.
Proven experience troubleshooting network connectivity issues, BGP routing, and GRE tunnels, and performing packet capture analysis
Confident with command line and tools, including curl, dig, traceroute, openssl, git
Experience in a web development and / or hosting environment such as installing and configuring web servers like Apache, Nginx, Caddy and IIS.
You are competent at writing scripts in Bash, Python, JavaScript or other scripting languages.
You have worked with PostgreSQL, MySQL, MS SQL, and other database servers.
Bachelor’s degree in Computer Science, Cybersecurity, or a related field (or equivalent experience).
Relevant certifications such as CISSP, GCIA GCIH, GCFA, GCFE or equivalent.
What Makes Cloudflare Special?
We’re not just a highly ambitious, large-scale technology company. We’re a highly ambitious, large-scale technology company with a soul. Fundamental to our mission to help build a better Internet is protecting the free and open Internet.
Project Galileo: Since 2014, we've equipped more than 2,400 journalism and civil society organizations in 111 countries with powerful tools to defend themselves against attacks that would otherwise censor their work, technology already used by Cloudflare’s enterprise customers--at no cost.
Athenian Project: In 2017, we created the Athenian Project to ensure that state and local governments have the highest level of protection and reliability for free, so that their constituents have access to election information and voter registration. Since the project, we've provided services to more than 425 local government election websites in 33 states.
1.1.1.1: We released 1.1.1.1 to help fix the foundation of the Internet by building a faster, more secure and privacy-centric public DNS resolver. This is available publicly for everyone to use - it is the first consumer-focused service Cloudflare has ever released. Here’s the deal - we don’t store client IP addresses never, ever. We will continue to abide by our privacy commitment and ensure that no user data is sold to advertisers or used to target consumers.
Sound like something you’d like to be a part of? We’d love to hear from you!
Please note that applicants who progress to the offer stage of the interview process may be asked to attend an in-person interview within one of the Cloudflare Offices or Cloudflare Hubs.  More details about this will be available at that stage of the interview process.
This position may require access to information protected under U.S. export control laws, including the U.S. Export Administration Regulations. Please note that any offer of employment may be conditioned on your authorization to receive software or technology controlled under these U.S. export laws without sponsorship for an export license.
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