Network Security Specialist

Overview

As a Network Security Engineer, you protect Liberty Global’s core tier-1 network from threats and ensure security is aligned with industry best practices. You work with global security and network teams to identify improvements, translate findings into risk-aware actions, and guide incident response. You will lead security enhancements across the core network and advise external networks on adopting consistent measures. Your role combines hands-on monitoring, escalation, and collaboration to strengthen network resilience and security posture.

Pay / Benefits

• Competitive salary + Bonus
• 25 days annual leave
• LinkedIn Learning & Coursera access
• Company Pension Contributions
• Calm subscription (NL)
• Public transport subscription (NL) for work and leisure travel

Responsibilities

• Serve as authority on Internet security topics (Network Hygiene, MANRS, DDoS mitigation, BGP routing, traffic analysis)
• Trace sources of BGP hijacks/Leaks, DDoS, malware, and abuse traffic
• Review and update security requirements in policies to align with best practices
• Identify improvement areas and drive implementation across networks
• Coordinate with Global Security Operations Centre and external teams for prioritization
• Engage with external bodies (M3AAWG, CableLabs, RIPE) to ensure adherence to security standards
• Translate security findings into risk assessments and actionable guidance
• Provide mentorship, act as escalation point for engineers
• Monitor and respond to security incidents
• Review and hand over monitoring use cases and runbooks to incident response teams

Key requirements

• Solid networking, security, and monitoring knowledge
• Experience securing large ISP networks
• Familiarity with BCP38/84, RPKI, BGP, DNS/DNSSEC, DDoS protection
• Understanding of vulnerabilities (DNSSEC, CoPP, access lists, TACACS, abuse)
• Experience presenting findings to operational teams
• Collaboration across internal/external teams in international contexts
• ISP environment and Internet security experience
• Experience with RIPE NCC, whois/RDAP, RIPE RIS, BGP, DNS monitoring preferred
• English fluency and superb communication
• Knowledge or interest in at least 4 areas from the listed tech stack

• Excellent communication
• Team player
• Independent under pressure
• Networking, TCP/IP, IPv4/IPv6
• BGP, RPKI, CoPP
• DNS/DNSSEC

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