Network Security Specialist

Liberty Global

Amsterdam, London
Full-time
5-10 years experience
On-site

Key Skills

Network security
ISP network protection
BGP routing
DDoS mitigation
Network hygiene
TCP/IP
IPv4/IPv6
DNS/DNSSEC
Security monitoring
Splunk
Arbor threat mitigation
Grafana
Elastic Stack
Scripting
Incident response
Technical leadership

Job Description

ABOUT US

We’re building Tomorrow’s Connections Today, bringing people together through the power of our technology.

Liberty Global is a world leader in converged broadband, video and mobile communications and an active investor in cutting-edge infrastructure, content and technology ventures.

With our investments in fibre-based and 5G networks we play a vital role in society, currently providing over 85 million fixed and mobile connections and rolling out the next generation of products and services, while readying our networks for 10 Gbps and beyond.

We’re creating national champions, combining the best broadband and mobile networks under brands such as Virgin Media-02 in the UK, VodafoneZiggo in The Netherlands, Telenet in Belgium, Sunrise in Switzerland, Virgin Media in Ireland and UPC in Slovakia.

Liberty Global Ventures, our global investment arm, has a portfolio of more than 75 companies and funds across content, technology and infrastructure, including strategic stakes in ITV, Univision, Plume, Lionsgate and the Formula E racing series.

Our scale enables us to transfer knowledge and expertise across our operations and investments, creating a dynamic family of brands united in the pursuit of innovation and excellence.

And we’re prioritising diversity, equity and inclusion in our workplace and communities, while reducing our impact on the environment. We are using technology as a force for good; for our people, our partners and the planet.

JOB PURPOSE

You will assure that our core and global tier-1 network has sound and industry best practice security protection and that the security of these products are monitored.

The role will work closely together with Liberty Global core network architects, engineering and operational and global security teams to identify improvements and drive Network Hygiene security improvements and provide specialized skills in case of investigations.

The role includes the ability to translate security findings or deficiencies to security risks and advise the organization on blocking issues and acceptable risk.

  • Identify and drive improvements on Network Security on the tier-1 core network of Liberty Global.
  • Identify and advise our ISP networks to implement similar security measures and monitoring.
  • Review and generate technical specifications/documentation
  • Translate, create, and hand over network monitoring use cases and tread play books to incident response teams
  • Act as a mentor, technical lead and escalation point for other engineers
  • Monitor and respond to incidents

KEY ACCOUNTABILITIES

  • Serve as an authority on Internet security related questions on topics like Network Hygiene, MANRS, DDoS mitigation, BGP routing and traffic analysis.
  • Trace and identify sources of BGP hijacks, BGP leaks, DDoS, malware or other abuse traffic
  • Review and update/improve security requirements set in policies/guidelines and make sure that these are following industry best practice.
  • Identify potential areas of improvement and drive implementation.
  • Liaise with the Global Security Operations Centre, LG and external operational teams and other Business units to have the right priorities set for maximum effect.
  • Work with and understand deliverables of external bodies like M3AAWG, CableLabs, RIPE, and other security and standards organizations to assure Liberty Global networks and services follow industry Best Practice regarding Security areas.

We tend to look for people with:

  • Solid grasp of Networking, Security and Monitoring
  • Experience and expertise in securing and protecting large (ISP) networks.
  • Familiarity with network hygiene measures such as BCP38/84 anti-spoofing protection, RPKI, and other BGP routing BCPs, RIRs, and Internet Routing Registries, DNS/DNSSEC, and domain registration.
  • Strong grasp of network security vulnerabilities and protections like: Denial of Service attacks and mitigation, BGP Hijacking, CoPP, access-lists, Tacacs, Spam/malware/abuse.
  • Experience in presenting findings and making recommendations to other operational teams.
  • Experience in working with many collaborators to improve security and incident response both internal and external in an international community.
  • Demonstrated ability in an ISP environment and Internet security arena.
  • Experience with Internet organizations like RIR's and domain name registries and tools like whois/RDAP, RIPE RIS, BGP and DNS monitoring. RIPE NCC certification (Database/BGP security) is a plus.
  • Solid understanding of network security, security monitoring, and layers of defense principles.

SKILLS & ABILITIES:

  • Fluency in English (speaking/writing)
  • Superb communication skills

Extensive knowledge or interest of at least 4 of the following areas:

  • Networking, TCP/IP, IPv4/IPv6 and main services used by applications
  • BGP, RPKI, Control Plane Policing (CoPP), DNS/DNSSEC
  • Protection against DOS attacks, amplification factors and mitigation techniques
  • Security analytics capabilities
  • Experience with monitoring and analytics solutions (e.g. Arbor threat mitigation suite, Splunk, Grafana, Elastic Stack etc…)
  • Basic scripting/programming/database skills.
  • A great teammate, able to prioritise effectively and work independently well under pressure.
  • Working with internal / external working groups to support improving network security and reduce impact of Denial of Service attack factors or other service disruptive activities in our footprint.

Some of the benefits we offer:

  • Competitive salary + Bonus
  • 25 days annual leave with the option to purchase 5 more
  • Free access to LinkedIn Learning & Coursera to continue to develop and grow your career with us
  • Company Pension Contributions
  • Free premium subscription to Calm – a renowned well-being & meditation app (NL only)
  • Free public transport subscription that can be used for both work and leisure travel on all modes of public transport, anywhere in the Netherlands
  • Subsidy on health insurance premium
  • Company Laptop, Mobile and Phone Subscription

Liberty Global is an equal opportunity employer. We embrace diversity and are committed to creating an inclusive environment for our people. We will ensure that individuals with disabilities are provided reasonable accommodation to participate in the job application or interview process. We’re 100% committed to having a workforce that represents every part of our society. So we’re keen to hear from candidates of all background and circumstances.

Core Responsibilities

You will ensure the security of the global tier-1 network by implementing industry best practices and monitoring for threats. The role involves collaborating with architects and engineering teams to drive network hygiene improvements and providing specialized expertise during security investigations.

Requirements

Candidates should have extensive experience in securing large ISP networks and a solid grasp of network security vulnerabilities and mitigation techniques. Proficiency in BGP, DNS, and network monitoring tools is essential, along with strong communication skills for presenting findings to operational teams.

Benefits

  • Competitive salary
  • Bonus
  • 25 days annual leave
  • LinkedIn Learning access
  • Coursera access
  • Company pension contributions
  • Calm app subscription
  • Free public transport subscription
  • Health insurance subsidy
  • Company laptop
  • Mobile phone subscription

About Liberty Global

Industry: Services for Renewable Energy

Company size: 51-200 employees

At Believ, we’re proud to be at the heart of your journey to cleaner, more sustainable travel. We’re building one of the UK’s most accessible, reliable, and future-ready EV charging networks – because no one should be left behind on the road to net zero. Whether you're a local authority planning your EV strategy, a landowner looking to unlock long-term value, a business aiming to attract more customers, or a driver who just wants a charger that works – we're here to make it simple, seamless and sustainable. 🩷 For communities: We deliver affordable, reliable, and intuitive on-street charging where it’s needed most. 🩷 For local authorities: We design and implement tailored EV infrastructure strategies at zero cost to councils, working in true partnership every step of the way. 🩷 For landowners and businesses: We turn land and locations into high-performing, future-fit charging hubs – at zero cost, helping increase footfall and revenue with flexible, commercially smart models. 🩷 For the planet: Our charge points run on 100% renewable energy, and we take full responsibility for what we build – delivering resilient, well-maintained networks built to last. We’re action-oriented. Straight-talking. And proudly collaborative – because delivering EV infrastructure that works for everyone takes more than ambition. It takes trust, scale, and real delivery. We’re not just installing charge points. We’re powering a movement – and we’re proud to be right there, at the heart of your journey.

Added 3 months ago