Network Security Engineer (Fortinet)

CACI Ltd; Birmingham; Hybrid; GBP 65,000 - 90,000; Full time

Job summary

CACI Network Services in London is seeking a Senior Network Security Engineer to join the Network Team. You will plan, deploy, and manage client network security projects, ensuring robust infrastructure and smooth change control.

The role requires Fortinet expertise, NGFW deployments, and strong routing/switching knowledge. You will document changes, create RFC plans, and collaborate with stakeholders in fast-paced environments. Hybrid working arrangements apply.

Qualifications

• Experience in network security deployment or migration.
• Ability to manage complex policies and rules.
• Experience deploying NGFW in hybrid cloud environments.
• Extensive Fortinet firewall experience.
• Knowledge of IDS/IPS, user-ID, SSL inspection.
• Design enterprise VPN hubs and high-availability tunnels.
• Good routing and switching knowledge.
• Strong stakeholder engagement and customer service mindset.
• Able to work in a fast-paced and demanding environment.
• Fortinet NSE certifications (NSE 4–7).

Responsibilities

• Plan, manage and deploy technology changes to support DC services.
• Deploy LAN infrastructure to support end user services.
• Create implementation plans for RFCs with detailed checks.
• Document back-out plans and identify back-out points.
• Support stability and uptime by planning changes.
• Identify changes with zero downtime and plan resource use.
• Document change risks and mitigation tactics.
• Document network estate with high-quality diagrams.
• Peer review and validate deployment plans.

Skills

NGFW deployment

Fortinet firewalls

IDS/IPS

SSL inspection

VPN hubs design

High-availability tunnels

Routing & switching

Stakeholder engagement

Problem solving

Hybrid cloud environments

NSE 4-7 Fortinet certs

Change management

Tools

Fortinet firewall management tools

Job description

From our headquarters in London, we’re busy empowering organisations to make bold, strategic moves with the power of data and technology. Founded in 1975, our operations take place from multiple offices across the UK, Europe and India with over 1600 full-time employees and an annual turnover of £179m.

Our expertise spans industries, from retail and education to public sector and transport – delivering intelligent solutions that drive progress and create measurable impact. Whether it’s business intelligence, customer marketing, cloud infrastructure, cybersecurity, critical national infrastructure or data management, our approach is never one-size-fits-all.

We don’t just deliver solutions; we build for the tomorrow’s world, all while fostering a culture that allows employees to be their authentic selves and succeed in their careers.

About Network Services

CACI Network Services is a rapidly expanding specialist IT and Networks consultancy offering a wide variety of opportunities to work within challenging and exciting environments with our major clients in Global Media, Banking, Government, Telecoms & Utilities

The role

A Senior Network Security Engineer is required to join the Network Team, responsible for the deployment and planning of our clients network infrastructure.

The team is responsible for the delivery and deployment of network/security projects and requests to enhance the client’s infrastructure to meet current and future business demands.

Key responsibilities

Plan, manage and deploy technology changes to support DC services

• Deploy LAN infrastructure to support end user services requirements
• Includes patching schedules for facilities to cable network equipment
• Diagrams for Network Operations
• Inventory management

Create implementation plans for RFC’s to a high level of detail.

• Correctly document pre and post checks for change verification purposes
• Understand and document back out plans, clearly identifying back out points.
• Identify points of no return

Support the stability and uptime of essential services by planning changes with a documented best approach mind set.

• Identify where changes can be complete with zero downtime to hosted services.
• Plan and implement changes with a cost effective resource strategy.

Identify, understand and document change risks and mitigation tactics.

• Identify, understand and document impact of planned technology changes, including documentation expected output from verification.

Document network estate for Operation Support and to support change planning

• Complete network diagrams to a high standard.

Peer review and validation of technical deployment plans

• Provide constructive feedback to peers to support change control requirement and maintain high standards of detail and quality offered by CACI.

Core skills, knowledge and experience required

• Experience working in a network security deployment / migration environment.
• Able to manage complex policies, user- or app-based rules.
• Experience in deploying NGFW in hybrid cloud environments.
• Extensive experience working on Fortinet firewalls.
• Able to implements IDS/IPS, user-ID, SSL inspection.
• Designs enterprise VPN hubs, multi-factor access, high-availability tunnels.
• Good knowledge of routing and switching.
• Strong Firewall Experience
• Ability to work in a fast paced and demanding environment.
• Good stakeholder engagement skills with a strong customer service mind set.
• Good time management skills to manage and action business as usual operational tasks as well as execute and deliver operational projects
• Well-developed problem solving skills, with the ability to assimilate data rapidly in order to present solutions effectively.
• Flexibility and agility to adapt to changing requirements.
• Holds Fortinet certifications (NSE 4 to 7)

Flexibility

The key to our success is our teamwork and collaboration. We take a hybrid approach – working remotely and coming into the office depending on the business demand and collaboration required as part of the delivery process.

Equal opportunities

CACI is proud to be an equal employer. Embracing the diversity of our people, we are on a journey to build a truly inclusive work environment where no one is treated less favorably due to ethnic origin, age, gender, veteran status, religion or belief, sexual orientation, marital status, and disability or health condition, actively working to prevent discrimination.