Network Engineer - Enterprise Infrastructure

Location: Hybrid – 4 days per week on site at MOD Corsham Rate: Up to £550/day IR35 status: Inside IR35 Contract dates: 01/10/2026 to 31/03/2028 Closing date: 15th September 2026 at 10:00 Security clearance: UK Security Clearance (SC) required Overview Our customer, a large defence organisation, is seeking an experienced Network Engineer to deliver hands-on engineering support to the OpNET programme, designing, building and supporting enterprise network infrastructure. The role focuses on physical and virtual networking technologies forming the backbone of the platform, supporting full lifecycle delivery from design and build through to integration, testing and operational support within secure or regulated environments. Programme Context The New Style of IT (Deployed) – NSoIT(D) – programme is delivering OpNET , a new C4 capability across the SECRET, Mission SECRET and OFFICIAL-SENSITIVE security domains. The programme aims to deliver a highly secure, technologically advanced and evolutionary communications and information service that connects war-fighters and enables information advantage across the operational landscape. Key Responsibilities Design, build and support enterprise network infrastructure across physical and virtual environments. Implement and manage core networking components including routers, switches and firewalls. Deliver network solutions aligned to modern architectures such as leaf-spine and software-defined networking. Support configuration and troubleshooting of routing protocols, including OSPF and BGP. Implement network services including IP addressing, subnetting, QoS and traffic management. Deploy and manage overlay and virtual networking technologies such as VXLAN. Support secure network implementations including firewall policies, IDS/IPS and secure communications. Produce and review technical artefacts including design documentation, build guides and operational procedures. Support system integration, testing and validation of network services. Work with Service Management to investigate and resolve incidents and service issues. Contribute to continuous improvement and standardisation of network services. Provide support for Live Ops as required. Essential Skills, Qualifications and Experience Strong experience in network engineering, including design, implementation and troubleshooting. Knowledge of IP networking fundamentals including subnetting and addressing schemes. Experience with routing protocols, including OSPF and BGP. Advanced knowledge of network devices including routers, switches and firewalls. Experience with enterprise network technologies, e.g. Cisco Nexus, IOS XE, leaf-spine architecture and VXLAN. Understanding of network security technologies, e.g. firewalls, IDS/IPS and AAA platforms. Experience with QoS and traffic management techniques. Ability to produce technical documentation, including LLDs, build guides and runbooks. Strong analytical, troubleshooting and communication skills. Relevant certification, e.g. CCNP or equivalent. Desirable Skills, Qualifications and Experience Experience working within Defence or secure public sector environments. Knowledge of defence networks and secure gateway architectures. Experience delivering within large-scale or virtualised infrastructure environments. Familiarity with Agile delivery and Atlassian toolsets, including JIRA and Confluence. Experience developing secure, multi-tenanted network architectures. Additional certifications, e.g. VCP-NV, CCIE, or Chartered Engineer status. Additional Information Base working site is MOD Corsham. 4 days per week on site are required. UK Security Clearance (SC) required. The assignment is expected to run from 1 October 2026 to 31 March 2028.