Senior Network Security Engineer

Janestreet; Greater London; On-site; GBP 90,000 - 140,000; Full time

Job summary

Jane Street is seeking an experienced Network Engineer to join our Network Security team in London. You will run, scale and continuously improve our security infrastructure through hands-on operations, design and implementation.

The role emphasizes collaboration across global teams, advanced networking, and security knowledge to deploy secure traffic flows, manage DMZs, and evolve monitoring and automation.

Qualifications

• 7+ years of experience operating and deploying network infrastructure.
• Experience with routing and network protocols (OSPF, BGP, PIM-SM).
• Troubleshooting transport protocols (TCP/UDP).
• Strong understanding of firewall hardware architecture and performance metrics.
• Experience with firewall configuration and troubleshooting.
• Understanding of Public Key Infrastructure and modern encryption techniques.
• Fluency in English.

Responsibilities

• Work closely with Network Engineering on design and deployment of security perimeter and adjacent network infrastructure.
• Effectively manage and continuously evolve network segmentation, DMZ, and other aspects of network security.
• Evaluate and lab test new platforms for our network security infrastructure.
• Collaborate with Cybersecurity on detection and mitigation of threats and vulnerabilities on our network.
• Interface with application owners and traders to enable business workflows in a secure way.
• Proactively enhance support by improving network infrastructure observability, scripting, and communicating requirements to our software engineers.
• Improve our network security processes and documentation.

Skills

7+ years experience

Routing protocols

Network security

Firewall expertise

PKI & encryption

English fluency

Automation & scripting

Job description

Jane Street is seeking an experienced Network Engineer to join our Network Security team in London. You will run, scale and continuously improve our security infrastructure through hands-on operations, design and implementation.

The role emphasizes collaboration across global teams, advanced networking, and security knowledge to deploy secure traffic flows, manage DMZs, and evolve monitoring and automation.