Network Architect (Security Clearance)

CGI; Reading; On-site; GBP 100,000 - 125,000; Full time

Job summary

A leading technology consultancy in Reading is seeking a Network Architect to lead network design and optimisation for secure, virtualised environments. In this full-time role, you will influence mission-critical infrastructure and collaborate with a skilled team to create cutting-edge solutions. Ideal candidates will have extensive experience with secure network architectures, proficiency in routing and switching, and enjoy a collaborative work environment. Competitive salary and benefits are offered.

Benefits

Competitive salary

Excellent pension

Private healthcare

Share scheme

Qualifications

• Experience designing and implementing secure network architectures.
• Knowledge of routing, switching, and firewall configurations.
• Ability to work in a collaborative environment.

Responsibilities

• Lead redesign and optimisation of network architectures.
• Produce HLD and LLD network designs.
• Collaborate with test teams for validation.
• Enhance network performance through best practices.
• Serve as a technical authority on network security.

Skills

Cisco

Firewalls

Network Architecture

Tools

Juniper SRX firewalls

Cisco Layer 2 switches

Dell switches

VMware virtualisation

Windows Server environments

Job description

Position Description

At CGI, we empower our technical experts to redefine what's possible in secure network design. As a Network Architect, you’ll play a key role in reimagining and modernising network architecture that underpins complex, air‑gapped, virtualised environments. Your work will directly influence mission‑critical infrastructure, ensuring resilience, scalability, and security across a highly secure programme. You’ll collaborate with a talented team of engineers and testers to deliver advanced, high‑performance solutions that enable transformation, innovation, and enduring success for our clients.

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. This is a full‑time, on‑site position based in Reading.

Your future duties and responsibilities

In this role, you will lead the redesign and optimisation of complex, multi‑environment network architectures, focusing on modernising connectivity across air‑gapped and virtualised infrastructures. You’ll take ownership of technical direction, ensuring secure, high‑performing designs that meet both client and programme objectives. Working closely with infrastructure, test, and security teams, you’ll produce high‑quality technical documentation and guide implementation through to validation and delivery.

You’ll have the opportunity to shape secure network solutions that balance innovation and reliability, collaborating within a supportive environment that values initiative, creative problem‑solving, and precision in execution.

Key responsibilities

• Lead & Innovate: Redesign existing network architecture integrating modern layer 3 switches, layer 2 switches, routers, and firewalls.
• Design & Deliver: Produce detailed High‑Level (HLD) and Low‑Level (LLD) network designs, ensuring alignment with secure system requirements.
• Collaborate & Support: Partner with test teams to provide consultation on appropriate test design and validation approaches.
• Optimise & Automate: Enhance network performance and reliability through modernisation and configuration best practice.
• Advise & Influence: Serve as a technical authority on network security, architecture, and system interconnectivity.

Required qualifications to be successful in this role

You should bring strong experience in designing and implementing secure, virtualised network architectures, with deep knowledge of routing, switching, and firewall configurations. A proactive, detail‑focused approach and the ability to work in a highly secure, collaborative environment are essential.

Essential skills and experience

• Proven experience designing and deploying complex, secure network architectures.
• Strong understanding of Layer 2 and Layer 3 switching and routing principles.
• Hands‑on experience with Juniper SRX firewalls (e.g., SRX240) and Cisco Layer 2 switches (e.g., Cisco 2960).
• Experience with Dell switches, VMware virtualisation, and Windows Server environments.
• Familiarity with Mini Catapans or similar air‑gapped networking solutions.
• Ability to produce detailed HLD/LLD documentation and collaborate effectively with testing and implementation teams.

Skills

• Cisco
• Firewalls
• Network Architecture

What you can expect from us

Together, as owners, let’s turn meaningful insights into action.

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.