Top Network Engineer Jobs in London

Lead delivery and performance management for Ericsson IMS and fixed voice core networks. Responsibilities include IMS design, deployment, optimization, parameter tuning, QoS and capacity audits, KPI analysis, upgrade impact assessments, troubleshooting, PCAP tracing, customer presentations, and technical governance. The role requires end-to-end knowledge of IMS and CS Core networks, strong Ericsson product expertise, customer handling, and hands-on experience with network planning and optimization.

Designs, commissions, configures, patches, and maintains IT infrastructure and networks, including servers, switches, firewalls, routers, and operating systems. Develops operational and security procedures, conducts testing, manages risks, supports stakeholders and suppliers, and trains maintenance teams. The role requires experience with virtualization, containerization, databases, Windows, Linux, and network security standards. It is hybrid in London or Cheltenham and requires existing UK SC clearance or eligibility to obtain it.

Own and improve corporate networks, infrastructure, workplace technology, and office systems. Provide advanced IT support, troubleshoot networks and endpoints, administer Cisco LAN/WAN environments and FortiGate firewalls, manage office hardware, improve device and access management, and collaborate on network security. Build monitoring, alerting, and documentation to maintain reliable business-critical systems across offices.

Designs, deploys, and supports global data-center and enterprise networks across financial sites. Delivers network projects, third-party service turn-ups, migrations, and platform refreshes. Leads routing, switching, EVPN/VXLAN, incident escalation, root-cause analysis, automation, monitoring, infrastructure upgrades, and network audits. Requires expertise across Juniper, Arista, and Cisco platforms, plus Python and Ansible automation. The role also mentors junior engineers and coordinates technical handovers across global regions.

Maintain and troubleshoot edge network infrastructure for managed-service customers, including firewalls, routing, switching, wireless networks, and VoIP systems. Process firewall and routing changes, investigate connectivity and performance issues, support Cisco Firepower and Call Manager environments, perform break/fix replacements, and document processes. The role requires strong communication and problem-solving skills, with Cisco certification and CompTIA networking or security credentials advantageous.

Designs, deploys, and supports high-performance, low-latency networks and data center connectivity. Automates network configuration and observability using Ansible and Terraform, supports broader infrastructure, manages vendors and circuit providers, and plans data center work. The role requires coding ability, network and systems administration experience, routing and switching knowledge, Linux proficiency, firewall automation, troubleshooting skills, and familiarity with monitoring and testing tools.

Leads enterprise proxy, perimeter, and SSE/SASE security engineering across US operations. Designs and operates Zero Trust, identity-aware proxy, secure gateway, egress, segmentation, and cloud interconnect architectures. Owns roadmap execution, governance, remediation, lifecycle modernization, incident management, observability, and resiliency. Supervises engineers, establishes reusable security patterns, coordinates cross-functional delivery, and promotes secure, responsible AI-assisted engineering practices.

Provides technical support and guidance to game developers and publishers using PlayStation network services, APIs, tools, and technologies. Investigates and escalates technical issues, collaborates with internal and regional teams, gathers partner feedback, improves developer-facing tools and documentation, automates workflows, and delivers technical training and presentations.

Designs, implements, operates, and maintains Marex’s global network infrastructure. Responsibilities include network consultancy, operational support, security design, troubleshooting, vendor management, cloud networking, automation, infrastructure as code, and reporting. The role supports WAN, campus LAN, firewalls, exchange connectivity, and low-latency networks while ensuring regulatory compliance and operational resilience.

Own and improve enterprise IT and OT network strategy across multiple regions. Define network architectures, standards, documentation, security controls, and lifecycle practices. Lead design reviews, change control, audit support, segmentation, firewall integration, performance reporting, incident investigation, and service-provider coordination. Provide technical leadership for routing, switching, wireless, WAN, VPN, and network availability while supporting compliance, secure operations, and critical data centre environments.

Design, build, automate, and operate cloud-native network infrastructure to ensure reliability, performance, and observability. Drive test-driven infrastructure changes, support office networking, participate in on-call rotations, incident escalations, code/config reviews, and produce documentation and playbooks for the engineering organization.

Deliver live incident containment and recovery, security assessments, hardening, and managed security solution implementations for clients. Review and secure cloud, identity, firewall, endpoint, and network environments; design Zero Trust, SASE, segmentation, conditional access, and DLP solutions; preserve evidence and support forensic teams; and produce security architecture, deployment, and operational documentation.

Designs, supports, secures, and troubleshoots client and internal WAN/LAN infrastructure, routers, switches, firewalls, IP addressing, VLANs, and Cisco telephony systems. Provides advanced service desk support, handles customer escalations and change requests, documents technical changes, supports network projects, and participates in maintenance activities. The role also manages Cisco Unified Communications Manager, Unity Connection, CUBE gateways, and SIP endpoints while collaborating with customers and engineering teams.

Leads the design, deployment, operation, and optimization of enterprise network security platforms across AWS and on-premises environments. Builds infrastructure automation with Terraform, Python, and Ansible; integrates security controls into CI/CD pipelines; resolves complex infrastructure issues; and supports resilience, compliance, governance, and incident management. Acts as a technical authority, mentors engineers, collaborates with cloud and cybersecurity teams, and helps define network security strategy and standards.

Leads requirements capture, telecom tendering, and end-to-end network connectivity solution design across EMEA. Develops resilient architectures, high- and low-level designs, network diagrams, and governance documentation. Evaluates vendors, manages supplier performance and SLAs, embeds operational risk controls, and supports regional network strategy. Partners with business stakeholders, engineering teams, sourcing groups, and telecom providers while mentoring engineers and evaluating emerging connectivity technologies.

Maintain and improve enterprise network infrastructure, own network systems and core services, troubleshoot escalated issues, support projects and change delivery, contribute to design and automation (IaC), remediate security vulnerabilities, and collaborate with stakeholders to drive performance, resilience and service improvements.

Build and operate Internet-scale systems terminating HTTP and TLS, migrate infrastructure from NGINX to a Rust-based proxy, improve protocol performance, and contribute to open-source projects and industry standards. The role involves complex systems programming, reliable and secure software development, and collaboration with leading networking engineers.

Own end-to-end network design and delivery for GPU infrastructure deployments. Translate customer requirements into network, cabling, and rack plans; coordinate third-party physical build partners remotely; validate deployments; manage five or more concurrent projects; troubleshoot post-deployment issues through customer handover; and select appropriate vendors and technologies.

Build, operate, and scale CrowdStrike's global backbone and hybrid cloud networks. Design and implement IP and optical solutions, drive capacity planning, evaluate technologies, automate with IaC and CI/CD, support cloud networking, lead projects from ideation to implementation, and participate in 24x7 on-call rotation.

Design, implement, operate, and troubleshoot CrowdStrike’s global multi-vendor, multi-cloud, hybrid data center networks. Build cloud connectivity and network constructs, develop infrastructure-as-code and automation using Ansible, Terraform, Python, and Go, improve resilience and deployment efficiency, support incident analysis and on-call rotations, and ensure compliance with regional data sovereignty and security requirements.

Build, deploy, and operate highly scalable Network Services systems on Cloudflare’s global edge network. Develop distributed networking systems involving BGP, Linux kernel dataplanes, control planes, APIs, traffic analytics, and data pipelines. Improve system performance, reliability, and scalability while solving complex customer problems. Own solutions end to end across design, development, deployment, and operations, and collaborate across engineering and product teams.

Monitor autonomous satellite laser ranging stations, triage faults, coordinate fixes with field engineers and host sites, and maintain reliable network operations. Build dashboards, alerting, and runbooks; track network performance; report results to internal teams and customers; support tracking schedule planning; and help develop on-call coverage as the global station network expands.

Architect, engineer, and oversee delivery of complex corporate, colocation, and ultra-low-latency trading networks. Responsibilities include lifecycle management of switching, firewalls, load balancers, telemetry, CMDB, and automation platforms; designing software-driven network solutions; managing WAN traffic prioritization and steering; collaborating with project teams and vendors; and maintaining expertise in emerging networking technologies.

Architects, designs, manages, and supports enterprise network, telecommunications, video, and infrastructure systems. Responsibilities include network architecture, firewalls, routing, switching, wireless, load balancing, security, disaster recovery, vendor management, troubleshooting, infrastructure projects, compliance, third-level support, documentation, and technical training. The role also performs rotational on-call duties and serves as the network team’s highest technical resource.

Provides deep technical leadership for QRT’s global trading and enterprise networks. Leads complex investigations involving performance, latency, resilience, and operations; serves as a senior escalation point; translates architecture standards into automation, validation, documentation, and runbooks; supports migrations and technical improvements; evaluates technologies; develops instrumentation; and mentors network engineers.