Published on 26/08/2026

PERMANENT CONTRACT / SII United Kingdom

MISSION

We are seeking an experienced VIRTUAL ROUTING SYSTEMS ENGINEER to support the development, integration, testing and validation of software-defined routing solutions within secure and mission-critical environments.

The successful candidate will contribute to the design, development and verification of virtualised networking capabilities, supporting the delivery of next-generation routing and network management solutions. The role requires a strong software engineering background combined with hands-on experience of network protocols, virtualised environments and system-level testing.

Experience within the Defence, Aerospace, Communications or Secure Government sectors is highly desirable.

PROFILE

KEY RESPONSIBILITIES

Develop, integrate and maintain virtual routing and network management software components.

Support the design and implementation of software-defined networking (SDN) solutions and virtualised network functions (VNFs).

Develop and execute verification and validation activities for routing, switching and network management functionality.

Create automated test frameworks, test scripts and regression test suites.

Conduct functional, integration, system and performance testing of virtual routing platforms.

Analyse network behaviour and troubleshoot complex routing, protocol and interoperability issues.

Support the development and optimisation of IP networking services within virtualised environments.

Validate routing protocols and services including OSPF, BGP, RIP, ISIS, MPLS and multicast technologies where applicable.

Develop and maintain software and test documentation including design descriptions, test specifications and test reports.

Conduct protocol analysis using industry-standard tools and packet capture technologies.

Support system integration activities with wider platform, communications and security teams.

Participate in configuration management, software release and deployment activities.

Contribute to secure-by-design principles and support cyber security assessments.

Collaborate with customers and stakeholders to define acceptance criteria and support qualification activities.

Support defect investigation, root cause analysis and corrective action implementation.

EXPERIENCE REQUIRED

Proven experience in software development, integration or testing of networking systems.

Strong understanding of IP networking fundamentals and routing technologies.

Experience working with virtualised network environments and software-defined networking architectures.

Experience creating and executing structured test procedures and automated test frameworks.

Knowledge of networking protocols such as: TCP/IP, UDP, OSPF, BGP, VLA, MPLS, Multicast

Experience using Linux-based development environments.

Experience with network analysis and troubleshooting tools such as Wireshark, tcpdump or equivalent.

Understanding of software development lifecycle (SDLC) and configuration management processes.

Experience producing technical documentation, test specifications and verification evidence.

Strong problem-solving and analytical skills.

DESIRABLE SKILLS

Experience developing or testing military, defence or mission-critical communication systems.

Knowledge of software-defined networking technologies and frameworks.

Experience with Kubernetes, Docker or containerised networking solutions.

Familiarity with network function virtualisation (NFV) architectures.

Experience working within Agile or DevSecOps environments.

Knowledge of secure communications systems and cyber security principles.

Experience with automated CI/CD pipelines and test automation frameworks.

Familiarity with requirements management and systems engineering processes.

Understanding of MOD, NATO or defence communication standards.

Experience working in classified or secure development environments.

Current or previously held UK Security Clearance (SC or DV).

OUR AGENCY

With five strategic offices in Belfast, Chester, Farnborough, London and Oxford, we work in partnership with our customers UK-wide to deliver high-impact engineering solutions.

SII UK is a trusted Aerospace and Defence engineering partner, supporting the delivery of complex, mission-critical programmes while helping to shape the future of innovation across next-generation systems and technologies.

Our teams contribute daily to creating a fulfilling, stimulating and career development focused work environment.

True to our human-centred values, we are committed to making SII UK a Great Place To Work®, having been certified 5 years running.

Joining SII UK means being part of our collective goals, guided by our mission “Let’s Tech Together,” and helping to build a digital future that is sustainable, at the heart of an environment that values learning & collaboration.

SII GROUP

Who are we?

With five strategic offices in Belfast, Chester, Farnborough, London and Oxford, we work in partnership with our customers UK-wide to deliver high-impact engineering solutions.

SII UK is a trusted Aerospace and Defence engineering partner, supporting the delivery of complex, mission-critical programmes while helping to shape the future of innovation across next-generation systems and technologies.

Our teams contribute daily to creating a fulfilling, stimulating and career development focused work environment.

True to our human-centred values, we are committed to making SII UK a Great Place To Work®, having been certified 5 years running.

Joining SII UK means being part of our collective goals, guided by our mission “Let’s Tech Together,” and helping to build a digital future that is sustainable, at the heart of an environment that values learning & collaboration.

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