Senior Network Engineer in Stevenage

Join a brand-new team shaping the future of Defence and Space. We’re building a new team of Senior Infrastructure Engineers, including Network Engineers & IAM / IDAM Engineers to deliver a transformative integration project that will redefine infrastructure across our Aerospace, Defence & Security sector. We’re seeking skilled Infrastructure Engineers with deep expertise in network engineering to support the implementation of a secure, fully functional on‑premises domain for a leading Defence and Space client.

You’ll be responsible for executing a pre‑approved infrastructure design, with a particular focus on network architecture, connectivity, and security. This role demands hands‑on experience with enterprise‑grade networking technologies, secure routing and switching, and integration with authentication and directory services. You’ll collaborate closely with architects, other infrastructure teams, and client stakeholders to deliver a resilient and compliant network foundation.

You will be office‑based at one of our sites in Stevenage, Portsmouth, or Newport, with some flexibility to work from home. We can offer great career progression opportunities, ability to be based anywhere across the UK, benefits which you can flex to meet your needs and training and development opportunities.

What you’ll be doing:

• Implement Network Infrastructure Design – Deploy and configure network components in line with a pre‑approved architecture, ensuring performance, scalability, and Defence‑grade security.
• Secure Network Configuration – Configure firewalls, routers, switches, and access control lists (ACLs) to enforce segmentation, traffic filtering, and secure communication across the domain.
• Domain Connectivity & Integration – Support the integration of network services with Active Directory, DNS, DHCP, and certificate services to enable seamless domain functionality.
• Monitoring & Troubleshooting – Implement network monitoring tools, diagnose connectivity issues, and optimise performance across LAN / WAN environments.
• Security & Compliance Enforcement – Apply regulatory and client‑specific security controls, including encryption, IDS / IPS, and logging mechanisms.
• Stakeholder Collaboration – Work alongside infrastructure architects, other infrastructure teams, and client‑side stakeholders to ensure smooth implementation and rapid issue resolution.
• Documentation & Handover – Produce detailed network diagrams, configuration documentation, and operational procedures to support long‑term maintenance and knowledge transfer.

What you’ll bring:

• CCNA accreditation
• Strong knowledge and experience with Cisco technologies, including:

• Routing / Switching (IOS / NX‑OS)
• Firewall skills – Cisco ASA
• Data and Voice Cable Installation, Patching / Jumpering and Fault Finding
• Experience with infrastructure tooling such as OTDR and Cat5 / 6 cable test equipment

Would be great if you had:

• Prior experience in Defence, Aerospace, or Government projects
• Familiarity with network tooling such as Cisco Prime, Ops View (or similar)
• Working knowledge of Cisco Wireless networking applications and devices
• Exposure to Zero Trust principles and secure enclave architectures

If you are interested in this role but not sure if your skills and experience are exactly what we’re looking for, please do apply, we’d love to hear from you!

Employment Type: Full‑time, Permanent

Location: Stevenage, Portsmouth or Newport

Security Clearance Level: Eligible for SC Clearance

Salary: £60,000

Benefits: 25 days annual leave with the choice to buy additional days, health cash plan, life assurance, pension, and generous flexible benefits fund.

Although this role is advertised as full‑time, we believe that flexibility at work can promote work / life balance, increase your motivation, reduce stress and improves performance and productivity. We support different ways of working and can offer a range of flexible working arrangements.