Senior Specialist Engineer - Networks

Service Management, Automation & Technical Leadership

• Lead the monitoring, observability, performance and capacity management of network services, integrating operational and security monitoring with ITSM and SIEM platforms.
• Drive network automation and Infrastructure as Code using tools such as Ansible and Python to improve consistency and efficiency.
• Manage vendor relationships, technology lifecycles, procurement planning and proof-of-concept evaluations.
• Produce technical documentation, support ITIL Incident, Problem, Change and Request Management processes, contribute to CAB activities, mentor engineers, provide expert stakeholder advice, maintain compliance with ICT standards and deliver high-quality customer support, including participation in on-call and out-of-hours services.

This is not an exhaustive list.

Own and maintain a comprehensive and current understanding of the network architecture, acting as an authoritative technical reference for network design decisions. Maintain consistent availability and performance across specialist network systems, collaborating with other specialist engineers and ICT colleagues as required. Act as a primary network technical authority during major incidents, coordinating resolution activity across multi-disciplinary teams including infrastructure, security, application, and service management functions. Act as a technical point of expertise, providing advice, guidance, and training to improve and enhance services for end users. Support the Network Team in ensuring hardware, software, and associated technologies are designed, procured, and delivered efficiently and cost-effectively. Contribute to and lead the production of network architecture documentation, including High Level Designs (HLD), Low Level Designs (LLD), and As-Built records.

Network Architecture, Design & Delivery

Act as the senior technical lead for UKHSA network architecture, owning and maintaining High Level Designs (HLD), Low Level Designs (LLD), topology diagrams and As-Built documentation. Lead the design, implementation and lifecycle management of resilient, scalable and secure LAN, WAN, WLAN and cloud-connected infrastructure, ensuring alignment with NCSC Secure by Design principles. Provide technical assurance across estate modernisation, science campus, data centre and hybrid cloud programmes, while collaborating with infrastructure, security, application and cloud teams. Manage routing, switching, wireless, WAN, load balancing, IPAM, DNS and DHCP services, alongside Extreme Networks Fabric Engine, Site Engine and wireless platforms.

Network Security, Resilience & Incident Management

Provide technical leadership for network security and operational resilience across the UKHSA estate. Administer Palo Alto NGFW, Panorama, VPN, micro-segmentation, DMZ and Zero Trust architectures, ensuring compliance with security standards and evolving threat landscapes. Act as the senior network authority during Major Incident Response Team (MIRT) activities, leading diagnosis, resolution, communication, Root Cause Analysis (RCA) and Post Incident Reviews (PIR). Develop incident runbooks, continuity plans and mitigation strategies to reduce risk, improve service resilience and support secure cloud and on-premises environments.

Service Management, Automation & Technical Leadership

Lead the monitoring, observability, performance and capacity management of network services, integrating operational and security monitoring with ITSM and SIEM platforms. Drive network automation and Infrastructure as Code using tools such as Ansible and Python to improve consistency and efficiency. Manage vendor relationships, technology lifecycles, procurement planning and proof-of-concept evaluations. Produce technical documentation, support ITIL Incident, Problem, Change and Request Management processes, contribute to CAB activities, mentor engineers, provide expert stakeholder advice, maintain compliance with ICT standards and deliver high-quality customer support, including participation in on-call and out-of-hours services.

This is not an exhaustive list.

Person specification

Essential Criteria

• Formal technical qualification equivalent to CCNP level or above, or substantial experience in a senior network engineering role, with advanced knowledge of enterprise routing and switching, network security, wireless technologies, and large-scale network infrastructure management.
• Proven experience producing and maintaining network architecture artefacts, including High Level Designs (HLDs), Low Level Designs (LLDs), topology diagrams, reference architectures, and As-Built documentation across enterprise LAN, WAN, WLAN, and security environments.
• Demonstrable ability to lead or contribute to network architecture initiatives, provide technical assurance and design reviews, and ensure solutions align with organisational standards, security-by-design principles, and best practice methodologies.
• Significant experience acting as a senior technical authority during major incidents, leading network diagnosis and resolution activities, collaborating within multi-disciplinary Major Incident Response Teams, and managing complex, high-pressure situations.
• Experience producing Root Cause Analysis (RCA) reports, Post-Incident Reviews (PIRs), and maintaining incident runbooks, playbooks, and escalation procedures while driving continuous service improvement and reducing recurrence of critical incidents.
• Skilled in monitoring network infrastructure to optimise performance, support capacity planning, identify risks, and proactively address technical issues to maintain service availability and resilience for large user populations.
• Excellent written, verbal, reporting, and presentation skills, with the ability to communicate complex technical concepts to both technical and non-technical audiences, work effectively across multidisciplinary teams, deliver outstanding customer service, and manage competing priorities under changing timescales.

Desirable criteria

• Experience with network Function Virtualisation (NFV) and Software Defined Networking (SDN) architectures, including overlay/underlay design models and virtual network appliance deployment.
• Experience with advanced network automation toolchains including Terraform, Ansible, or Python-based frameworks applied to infrastructure provisioning and compliance enforcement.
• Hands-on experience with SIEM platforms (e.g. Splunk, Microsoft Sentinel) in the context of network security monitoring, alert triage, and threat hunting.
• Experience with Zero Trust technologies such as Zscaler ZIA/ZPA, Illumio, or equivalent ZTNA platforms in an enterprise deployment context.
• Familiarity with network observability tools such as ThousandEyes, NetBrain, or Datadog Network Performance Monitoring for advanced path analysis and synthetic monitoring.
• Experience with ITSM platforms (e.g. ServiceNow or equivalent) including use of the platform for major incident management, problem records, and change advisory workflows