Network Security Engineer

Location: Basingstoke (Hybrid - 2-3 days on-site per week)

Salary: Up to -60,000 + 10% bonus

83zero are proud to be working with a leading global organisation, headquartered in Basingstoke, who are on the lookout for a Network Security Engineer to join their Central IT division. This business operates within a secure and highly regulated environment and are looking for a technically skilled professional to help maintain and enhance their critical network infrastructure.

As a Network Security Engineer, you''ll play a vital role in the build, support, and evolution of complex networking systems, ensuring resilience, security, and performance across their production, pre-production, and development environments. You''ll work closely with the Infrastructure and Security teams to both proactively manage the network and support ongoing security initiatives.

Key Responsibilities:

• Provide technical support and network configuration across LAN, WAN, WLAN, VPN, firewalls, and intrusion prevention systems
• Maintain and support Cisco, HP, and Check Point hardware/software
• Respond to service requests and incidents in line with ITIL processes
• Monitor and enhance network security controls including web security gateways, NAC, endpoint security, and perimeter defense
• Contribute to internal reviews, security audits, vulnerability assessments, and penetration testing
• Support firewall rule changes, VPN access, network segmentation, and performance improvements
• Participate in on-call rotation for high-priority issues and assist during major incidents
• Create and maintain documentation including SOPs and security protocols
• Support IT security team with threat modelling, remediation, and policy compliance

Essential:

• Strong background in network engineering and troubleshooting across complex environments
• Operational knowledge of LAN/WAN infrastructure, routing protocols (OSPF, BGP, EIGRP), VPN (IPSec, IKE, SSL), and firewall configuration
• Experience working in secure environments with a focus on proactive security posture
• Knowledge of network security tools such as Cisco Secure Access, Cisco ISE, Microsoft Defender XDR, Sentinel, and SentinelOne
• Comfortable with vulnerability management frameworks and tools
• Familiarity with network monitoring and performance management
• Previous experience working within an ITIL-based support framework
• Hands-on experience with Check Point, Cisco, or Palo Alto firewalls

Desirable:

• Certifications such as CCNA, CCNP, CISSP, or equivalent
• Experience with Citrix load balancing and Microsoft Azure networking
• Knowledge of WAF technologies
• ITIL Foundation certification