Budapest Network Security Specialist 1117

Job description

Recruiter: Viktoria Pálfi-Vincze Hiring Manager: Stefan Reuter Career Grade: D About BT BT Group is the UK’s leading communications group and the holding company behind some of the country’s most recognised brands – including BT, EE, Openreach and Plusnet. Our purpose is as simple as it is ambitious: we connect for good. Our customers include consumers, small, medium and large businesses, public sector organisations and other communications providers. BT Group’s role is about setting direction, unlocking value and creating the conditions for our brands and businesses to thrive. Having come through the most capital-intensive phase of our fibre investment, our focus now is on what comes next – simplifying how we operate, using technology and AI to work smarter, and organising ourselves to serve customers better and grow sustainably. Group teams shape strategy, policy, brand, capital allocation and transformation, helping the whole organisation perform at its best. We have a singular culture that unites all our people: we are customer-first challengers, who are committed, clear and connected. These behaviours unite us as one team to deliver for our colleagues, our customers, our stakeholders and the country. Joining BT Group means working at the heart of a business that matters to the UK, with the opportunity to shape decisions, influence outcomes and help set the future course of one of the country’s most important companies. About the role • Specific business area: Managed Security. • Impact of the role: The Network Security Specialist operates as a third-line technical authority within Security Operations, upholding the highest standards of technical expertise and acting as the final internal escalation point before vendor engagement. The role leads the technical investigation and resolution of complex incidents, • looking beyond the immediate boundaries of network and next-generation firewall issues to identify wider network, security, service, and infrastructure dependencies and determine root cause, impact, and the most effective path to resolution. As a cornerstone of the technical support provided to the second-line team, the specialist delivers dependable escalation support, shares knowledge, strengthens technical capability, and enables colleagues to resolve incidents with greater confidence, consistency, and independence. The role also participates in the on-call rota, providing out-of-hours support for critical incidents and planned changes when required. • Link to strategy: Show how the role supports organisational priorities. What you will be doing (Role Accountabilities) • Act as the third-line authority for Data/Security/Voice Services and the final escalation before vendor engagement. • Resolve complex firewall, VPN, routing, connectivity, high-availability, policy, and management-platform incidents. • Assess incident scope, impact, priority, contributing factors, and the path to service restoration. • Analyse logs, packet captures, sessions, routing, configurations, and device health. • Investigate dependencies across WAN, LAN, DNS, DHCP, authentication, cloud, MPLS, SIP, and remote-access services. • Own complex incidents through investigation, recovery, validation, communication, and closure. • Plan, implement, validate, and document approved firewall changes and deployments. • Review change risk, dependencies, implementation steps, testing, and rollback plans. • Provide escalation support, technical guidance, and knowledge sharing to second-line teams. • Engage vendors with clear evidence and coordinate their activity through resolution. • Maintain investigation records, change outcomes, known errors, runbooks, and technical documentation. • Work with customers, suppliers, stakeholders, and technical teams to coordinate service delivery. • Support reporting, technical assurance, problem investigation, and continuous service improvement. • Support ISO/IEC 27001 compliance through evidence, reviews, and control improvements • Configure and expand networks, services and applications • Lead vulnerability, patch, and release management activities to maintain the security, stability, and availability of complex network and security environments. • Design and develop project-specific network and security architecture solutions, ensuring alignment with customer requirements, operational objectives, and industry best practices. • Deliver security consulting and professional services engagements tailored to customer needs, including the planning and execution of advanced Proof of Concepts (PoCs) to validate the performance, security, and integration capabilities of BT services and solutions. What you’ll need to succeed (Skills & Experience) Technical Knowledge • Expert knowledge of next-generation firewalls, including policies, NAT, VPN, routing, high availability, security profiles, and centralised management. • Advanced knowledge of TCP/IP, routing and switching, DNS, DHCP, LAN/WAN, SD-WAN, IPSEC, SIP, and the OSI model. • Strong understanding of remote access, DMZs, cloud connectivity, authentication, web security, and network segmentation. • Expert diagnostic skills using logs, packet captures, sessions, routing tables, configurations, and device-health data. • Detailed knowledge of incident, problem, and change management. • Strong understanding of operational risk, service continuity, rollback, recovery, and technical assurance. Experience & Skills • Significant third-line experience supporting complex next-generation firewall environments, preferably Fortinet and Meraki. • Significant third-line experience supporting complex network/MPLS environments, preferably Cisco and Juniper (JUNOS) • Proven ownership of high-impact incidents from deep investigation through recovery, root-cause identification, and closure. • Experience planning and deploying complex firewall and network changes with clear validation, risk, and rollback controls. • Ability to analyse issues beyond the firewall and coordinate resolution across network, infrastructure, cloud, and supplier teams. • Sound technical judgement under pressure, with the confidence to make decisions during critical service incidents. • Experience engaging vendors with complete evidence and driving technical cases through to resolution. • Strong communication, stakeholder management, technical writing, and customer-facing skills. • Proven ability to coach second-line teams, share knowledge, and improve runbooks and operational practices. • Commitment to continuous professional development and maintaining current, expert-level technical knowledge. • Ability to manage competing priorities and provide dependable on-call support for critical incidents and changes. BT Group’s Behaviours Customer First Prioritize customer needs in every decision and action. Challengers Challenge the status quo and bring innovative ideas to life. Committed Own outcomes and deliver with integrity. Clear Communicate openly and simply, ensuring alignment. Connected Collaborate across teams to achieve shared goals. Join us at a pivotal moment for BT Business. We are executing a multi-year transformation to restore growth, modernise at scale and unlock new markets beyond connectivity. Our ambition is clear – return to sustainable revenue and EBITDA growth, strengthen our market position, and deliver meaningful shareholder value through disciplined execution and bold reinvention. We are fundamentally reshaping the business – simplifying our portfolio, digitising our customer experience and building market-leading capability across cyber, AI and managed services, all powered by the UK’s leading fixed and mobile networks. This is a shift from a legacy connectivity provider to a modern, solutions-led, AI-first business that can truly differentiate in a competitive and fast-moving market. With execution momentum building and a clear path to growth, the opportunity now is to scale what works, accelerate performance and full