Senior Network Engineer (DV Security Clearance)

CGI Group Inc.; Devizes; On-site; GBP 65,000 - 95,000; Full time

Benefits offered by this job

Competitive pension

Private healthcare

Share scheme

Job summary

CGI Group Inc. is seeking a Senior Network Engineer to own complex network operations, ensuring high availability, stability, and security across critical infrastructures.

You will shape scalable, future-proof solutions, collaborating with multidisciplinary teams to deliver value for mission-critical programmes. You will work on Dell OS10, Sonic, Cisco networking, Palo Alto firewalls, and NSX-T, with responsibilities spanning design, integration, and optimization to strengthen operational

Qualifications

• Proven experience as a senior network engineer in enterprise/defence environments.

Responsibilities

• Lead & Innovate: Provide advanced support and troubleshooting across Dell OS10, Sonic, Cisco, Palo Alto, and NSX-T technologies.
• Develop & Deliver: Contribute to network integration, solution design, and scalable infrastructure enhancements.
• Optimise & Automate: Manage BGP, VPN, spine-and-leaf architectures, and data centre patching to maintain high performance.
• Maintain & Enhance: Oversee IPAM and DNS, and optimise load-balancing solutions, particularly F5.
• Integrate & Secure: Support InfoBlox deployments and align network operations with wider infrastructure strategies.
• Collaborate & Guide: Mentor junior engineers and strengthen cross-team engagement.
• Support & Protect: Participate in the on-call rota to ensure fast, effective resolution of critical incidents.

Skills

Senior network engineering

Defence environments

Troubleshooting

Mentoring

Tools

Dell OS10

Sonic

Cisco networking

Palo Alto

NSX-T

BGP

VPN

Spine-and-leaf

F5

InfoBlox

DNS/IPAM

Job description

As a Senior Network Engineer at CGI, you will play a pivotal role in safeguarding and advancing the networks that power our clients' most critical missions. You will help shape resilient, secure, and scalable infrastructure while contributing to innovative integration and design projects that drive industry transformation. This role offers the chance to take meaningful ownership of complex challenges, collaborate with expert teams, and apply your creativity to deliver future-ready network solutions. Supported by CGI's strong engineering community, you'll make a lasting impact across high-value programmes while continuously growing your skills in a dynamic and trusted environment.

CGI was recognised in the Sunday Times Best Places to Work List 2025 and has been named a UK 'Best Employer' by the Financial Times. We offer a competitive salary, excellent pension, private healthcare, plus a share scheme (3.5% + 3.5% matching) which makes you a CGI Partner not just an employee. We are committed to inclusivity, building a genuinely diverse community of tech talent and inspiring everyone to pursue careers in our sector, including our Armed Forces, and are proud to hold a Gold Award in recognition of our support of the Armed Forces Corporate Covenant. Join us and you'll be part of an open, friendly community of experts. We'll train and support you in taking your career wherever you want it to go.

Due to the secure nature of the programme, you will need to hold UK Security Clearance or be eligible to go through this clearance.

Your future duties and responsibilities

In this role, you will take ownership of complex network operations, ensuring high availability, stability, and security across critical infrastructures. You will apply your expertise to both support and enhance network environments, driving improvements that strengthen operational resilience and client outcomes. Working closely with multidisciplinary teams, you will contribute to the design and integration of new solutions, using your creativity and judgement to deliver scalable, future-proof capabilities. Your decisions and insights will directly influence service quality, network performance, and the success of mission-critical programmes.

• Lead & Innovate: Provide advanced support and troubleshooting across Dell OS10, Sonic, Cisco, Palo Alto, and NSX-T technologies.
• Develop & Deliver: Contribute to network integration, solution design, and scalable infrastructure enhancements.
• Optimise & Automate: Manage BGP, VPN, spine-and-leaf architectures, and data centre patching to maintain high performance.
• Maintain & Enhance: Oversee IPAM and DNS, and optimise load-balancing solutions, particularly F5.
• Integrate & Secure: Support InfoBlox deployments and align network operations with wider infrastructure strategies.
• Collaborate & Guide: Mentor junior engineers and strengthen cross-team engagement.
• Support & Protect: Participate in the on-call rota to ensure fast, effective resolution of critical incidents.

To excel in this role, you should bring strong technical depth in enterprise and defence-grade networks, combined with the ability to troubleshoot, design, and integrate complex solutions. You should be confident working in high-availability environments and comfortable collaborating across teams to deliver secure, high-impact outcomes.

• Proven experience in a senior network engineering role.
• Strong background in defence environments.
• Expertise with Dell OS10, Sonic, Cisco networking, Palo Alto firewalls, and NSX-T.
• Deep understanding of spine-and-leaf architecture, BGP, VPNs, and data centre patching.
• Strong knowledge of DNS, IPAM, load balancing; F5 and InfoBlox experience highly desirable.
• Excellent analytical, troubleshooting, and communication skills.

Desired Qualifications:

• Understanding of cross-domain technologies (Tiger Traps, Garrison, OpsWat, NiFi).
• Familiarity with VMware infrastructure and Elastic monitoring.

Life at CGI is rooted in ownership, teamwork, respect and belonging.

Here, you'll reach your full potential because... You are invited to be an owner from day 1 as we work together to bring our Dream to life. That's why we call ourselves CGI Partners rather than employees. We benefit from our collective success and actively shape our company's strategy and direction. Your work creates value. You'll develop innovative solutions and build relationships with teammates and clients while accessing global capabilities to scale your ideas, embrace new opportunities, and benefit from expansive industry and technology expertise. You'll shape your career by joining a company built to grow and last. You'll be supported by leaders who care about your health and well-being and provide you with opportunities to deepen your skills and broaden your horizons. Come join our team-one of the largest IT and business consulting services firms in the world.