Salary: £75,000 - 75,000 per year Requirements: Extensive multi-site LAN/WAN experience. Advanced configuration skills on Cisco and Cubic platforms. Deep knowledge of BGP, MPLS, VPLS, and segmentation. High availability technologies (HSRP/VRRP equivalents). Experience with DNS, DHCP, NAT, and IP planning. Experience in secure or Defence oriented environments. ITIL-based service management. Cisco CCNP certification (required); CCIE desirable. ITIL v4 Foundation or above. Degree in Computer Science, Network Engineering, or equivalent experience. Responsibilities: Lead the design, configuration, and support of secure multi-site LAN/WAN/SDN infrastructure. Configure and optimise enterprise switching platforms (e.g., Cubic M3X S8G / S24G, Cisco ESS3300 based). Implement routing protocols including BGP, MPLS, VPLS, and HA technologies. Configure firewalls, VPNs, IDS/IPS, and boundary protection systems. Support virtualised routing and SDWAN technologies (Cisco Catalyst 8000V). Act as senior escalation point for complex incidents. Ensure compliance with MOD security standards and Secure by Design principles. Maintain documentation, diagrams, and CMDB records. Support accreditation processes (IT Health Checks, CCVAs). Contribute to network automation (Python, Ansible, PowerShell). Identify opportunities for architectural improvement. Technologies: Ansible CMDB Cisco Support ITIL LAN MPLS NAT Network PowerShell Python SDWAN Security DevOps JSP VMware More: We are a leading organisation involved in a major Defence programme, seeking a highly skilled Senior Network Infrastructure Engineer to join our team. This role is based in Caerphilly with travel to client and Ministry of Defence sites as required. We offer an attractive salary of 75,000 along with a comprehensive benefits package. You will play a crucial role in designing, implementing, and supporting secure, resilient network services in a mission-critical environment. last updated 10 week of 2026