Senior Network Engineer - Security

Job Description

This hybrid role offers a great balance of home and office working. You’ll join your colleagues in your local office at least 2 to 3 days a week.

As the UK’s largest fibre-only network, and its only proven wholesale challenger, we’re busy setting new standards for what digital infrastructure can and should be.

Designed from scratch for the internet, our network is greener, more reliable and ready for the future. The products we provide over it not only lead the market on speed, value and service, they help businesses to innovate, provide entire communities with a better foundation for their digital lives and support economic growth, locally and nationally.

What does that mean for you? The opportunity to make internet connections (and daily life) a whole lot better, for a lot of people!

Joining us as a Senior Network Engineer - Security 

You’ll be joining a forward-thinking Network Engineering team at the heart of our mission to build and secure the UK’s most advanced full-fibre network. This role is key to delivering robust, scalable security solutions that protect our infrastructure and support our rapid growth. You’ll work on cutting-edge technologies, contribute to strategic security initiatives, and help shape the future of secure connectivity.

You’ll receive a salary of up to £80,000, a performance related bonus, and a range of benefits to support you across your financial, physical and mental wellbeing.

This is some of what you can expect to be doing:

• Designing and delivering secure network solutions across our national fibre infrastructure
• Leading the implementation of Active Network Security tooling and frameworks
• Acting as a senior escalation point for complex network security incidents
• Enhancing risk and vulnerability management processes
• Collaborating with architecture and operations teams to embed security best practices
• Supporting forensic investigations and Tier 3/4 incident response

What you’ll bring to the role

You’ll be a seasoned network security professional with deep technical expertise and a proactive, solutions-driven mindset. You’ll also have:

• Strong experience in LAN, MAN, and WAN security within large-scale environments
• Proven knowledge of firewalls, IDS/IDP, SIEM, and other security technologies
• Excellent understanding of Layer 2/3 networking, including Ethernet, MPLS, and TCP/IP
• Experience with risk and vulnerability management frameworks
• Familiarity with security standards such as NIST, NCSC, or ISO27001

Diversity, Inclusion & Belonging

We’re a Times Top 50 Employer for Gender Equality. We’re endorsed by WORK180 and we’re a partner of Diversifying. We have pledged our commitment to the Armed Forces Covenant and we’re a Disability Confident Employer. Working together with our Employee Networks, we’re wholly committed to ensuring that our people’s voices are heard, and that everyone feels a sense of belonging and pride to be a part of CityFibre. If you’d like to explore our culture and values, check out The CityFibre Way.

What you can expect from us

We want to offer you all the support you need to thrive inside and outside of work. This means giving you the tools to grow your career with us, as well as a comprehensive benefits package that you can adapt to your lifestyle. This includes 25 days annual leave, a day off on your birthday, a day off to support a charity or organisation of choice, a range of wellbeing and savings initiatives including private medical insurance, and supportive family friendly and menopause policies.

Additional Information

We want to create a sense of belonging for everyone. We celebrate our differences and work to ensure everyone has the best chance to succeed, starting with our recruitment process. No matter your background, family or carer status, ethnicity, sexual orientation, religion, age, disability, gender, or gender identity, we welcome your application. If you need any support or reasonable adjustments throughout the application process, please email us at careers@cityfibre.com. We want to help!