Firewall Expert

• Strategic planning, detailed technical preparation and operational management of an email gateway migration in a security-critical government environment.
• Preparation of the technical specification and development of technical concepts and migration approaches in line with BSI requirements.
• Technical requirements management with business units, information security and operations.
• Coordination of external service providers, integrators and implementation partners; maintenance of project plans, milestones, resources, risks and dependencies.
• Regular reporting to project management, the program environment and internal stakeholders.

Migration of an existing application to a new IT infrastructure.

• Managed all project activities (infrastructure, applications, data, security, architecture)
• Planned complex network architectures with security requirements
• Designed and coordinated firewall configurations
• Planned and managed interfaces between ERP, cloud, and third-party systems
• Coordinated middleware solutions (e.g. SAP Integration Suite, MuleSoft, Boomi)
• Defined data flows, mapping rules, and integration architectures
• Managed data migrations and master data harmonization
• Coordinated with business departments, IT teams, service providers, and external partners
• Team size: International team of 35 employees – Germany | Poland | India | USA
• Languages: English

Tools: Microsoft Office (Word, Excel, PowerPoint, Project), Brainloop, Jira, Confluence, MS SharePoint

• Completed the integration of log sources into Microsoft Sentinel, including GCP workloads – centralized consolidation of all security-relevant events from Azure and GCP environments for complete end-to-end telemetry and comprehensive compliance evidence
• Developed custom rules and use cases based on the GFG Use-Case Library and the MITRE ATT&CK Matrix to cover company-specific threats and GFG-relevant scenarios with precise, mapped detection rules
• Tuned detection rules to minimize false positives, optimized detection thresholds, and modeled exceptions – enabling the SOC to work with relevant, prioritized alerts while reducing Mean Time to Detect/Respond
• Built SOAR capabilities in Sentinel by developing playbooks to automate recurring response processes such as containment, user and host isolation, and ticketing – shorter response times and 24/7 scalability
• Designed and built a log transformation solution to normalize and enrich incoming raw logs (GeoIP, CMDB, threat intelligence) and convert them into a consistent schema for high-performance KQL queries, use case logic, and correlations
• Managed Azure security through Azure Policies to enforce security and compliance standards, prevent drift, and continuously remediate deviations
• Operated the Defender XDR portal to link endpoint, identity, email, and SaaS signals with Sentinel findings, enable holistic incident triage, and orchestrate measures directly from XDR

Technologies: Microsoft Sentinel, Microsoft Defender XDR, Azure Policy, KQL, GCP, MITRE ATT&CK

As part of this project, the existing active network infrastructure was modernized and made fit for the future. The goal was to introduce a powerful, secure and scalable network and WLAN infrastructure, including a Network Access Control (NAC) solution to improve network security and centralized access control.

At the beginning of the project, a comprehensive requirements analysis was carried out, taking into account the technical, operational and security-related requirements of the hospital sites. On this basis, a technical tender was prepared for new switches, WLAN access points and the NAC solution.

The successful implementation of the project established a modern, standardized and secure network infrastructure that meets the growing requirements for availability, mobility and IT security in hospital operations.

Activities:

• Supporting the tender process, including technical evaluation of offers and bidder evaluation
• Leading and managing the entire project implementation
• Coordinating the project process with internal stakeholders, business units and hospital IT
• Managing external service providers during the implementation and installation of the systems
• Monitoring the implementation, including quality control, project acceptance and defect management
• Coordinating and managing communication between hospital IT and external service providers as part of the NAC implementation
• Managing escalations in the event of technical and organizational challenges
• Ongoing budget monitoring and control of project expenses and additional costs
• Preparing decision papers for management on project changes, additional services and risks

• Development and implementation of tailored information security strategies

• Introduction and further development of ISMS according to ISO 27001, BSI baseline protection, and other standards

• Risk management and creation of security concepts

• Consulting for KRITIS, PCI DSS, TISAX, and VdS 3473/10000

• Building and improving security organizations

• Creation and implementation of guidelines, policies, work instructions, and process descriptions

• Audit support and certification preparation

• Conducting trainings, workshops, and awareness campaigns

• Selection and consulting on the introduction of IT security solutions such as SIEM, DLP, IDS/IPS, firewalls, and encryption technologies

• Conducting penetration tests and vulnerability analyses

• Consulting on the selection, integration, and management of security architectures in complex IT environments

• Consulting on ITSM and managed security services and SOC

• Leading and managing complex projects to improve information security

• Process analysis, optimization, and management according to ITIL, ISO 27001, and cybernetics

• Introduction and quality assurance of management, documentation, and knowledge management systems

• Support in complying with regulatory information security requirements (e.g. GDPR, HIPAA, SOX, GMP, KRITIS)

• Development and implementation of risk analysis procedures

• Organizing initial response, forensic investigations, and organizational measures in the event of security incidents

• Designing and running targeted workshops on topics such as ISMS, IT risks, and current threat scenarios

• Awareness campaigns to promote security culture in companies

• Special trainings on ISO 27001, BSI baseline protection, KRITIS, and other relevant standards

• Simulations and exercises to prepare for information security incidents

• Interim management for leading information security projects or IT security organizations

• Taking on the role of an external CISO (Chief Information Security Officer)

• Support in developing and implementing IT security and corporate strategies

• Coaching and mentoring of managers in the field of information security

• Building and leading security departments as well as recruiting and qualifying employees

• Temporary assumption of management responsibility in critical situations

• Managed Microsoft Cloud Accelerator Factory (CAF) programs for global enterprise customers, ensuring Azure cloud implementations aligned with security, governance, and compliance best practices, including ISO 27001-aligned controls and cloud security frameworks.
• Managed complex global enterprise transformation programs with strong focus on project delivery, financial governance, budget control, planning, risk management, and executive reporting, ensuring delivery within scope, timeline, and budget.
• Led the implementation of e-invoicing solutions for Nestlé, coordinating finance, IT, business stakeholders, and external providers to ensure successful integration, testing, rollout, and delivery of electronic invoicing processes.
• Managed an Oracle-to-PostgreSQL database migration, coordinating technical teams, application owners, testing activities, dependencies, risks, and cutover planning to ensure a controlled and successful transition.
• Led cross-functional programs involving finance and payment-related processes, enterprise platforms, and system integrations, with strong stakeholder management across business, IT, vendors, and senior leadership.
• Delivered transformation programs in FMCG environments, including Nestlé, managing complex international stakeholder structures, third-party providers, governance, RAID management, and business-critical dependencies.

• Development of a comprehensive transformation model for IT departments and ITSM organizations, from operational stabilization through structuring and optimization to strategic advancement
• Design of a transformation matrix that connects development phases with the implementation activities Position, Focus, Model, Enable, Anchor and Develop
• Development of assessment, maturity and decision-making logic to determine the operational starting point, the appropriate entry point and the prioritized areas of action
• Structuring of an end-to-end approach from current-state assessment and target vision through operating model, roadmap and service modules to implementation and integration into steady-state operations
• Derivation of combinable consulting and implementation modules, including methods, deliverables, role models, governance structures and transformation paths
• Collection, structuring and prioritization of business requirements from the perspectives of IT management, service management and operational roles
• Translation of requirements into target visions, process and role models, decision criteria and traceable deliverables

Environment / Tools: ITIL 4, IT4IT, Operating Model Canvas, SIAM, maturity models Kanban

• Operation and further development of the network and security infrastructure.

• Monitoring, analysis and resolution of network and security incidents.

• Cross-department collaboration with other specialist teams for operations, further development and reporting.

• Firewall vulnerability analysis.

• Firewall rule approvals.

• Troubleshooting IP communication issues in the network and firewall infrastructure.

• Security-critical IT infrastructure, processing of personal data, compliance with legal regulations.

• Products: Palo Alto Networks Firewalls, Cisco ACI, Checkpoint Firewalls, F5

• Technologies: SDN, SDWAN, Cisco EPIC, Cisco ACI

Project management and process consulting in the field of Building Information Modelling (BIM)

• Modernization of a large-scale Java enterprise application*

The project is modernizing a complex enterprise application that has grown over many years. The existing Spring-based legacy system runs on Java 8, OSGi, and Eclipse RCP and is being gradually migrated to a modern, maintainable architecture with Java 25 and Quarkus.

Marcus works on analysis, architecture, refactoring, and implementation. One focus is on untangling historically grown structures and dependencies and on building a clean, sustainable Java and Quarkus technology stack.

Tools & technologies: Java 8, Java 25, Quarkus, Hibernate ORM with Panache, EclipseLink, OSGi, Eclipse RCP, Maven, JUnit, Mockito, REST, JSON, Git, Eclipse IDE, IntelliJ IDEA Ultimate, Jira, Confluence

Project: Process optimization & IT support in an insurance broker office.

Project activities:

• Analysis of processes and definition of requirements
• Consulting for the implementation of a cloud solution (soho)
• Installation and verification of new infrastructure HW
• Cloud installation & configuration
• Definition and creation of use cases
• Performing user acceptance tests (UAT)
• User training / training
• IT support (cloud, PC, server, printer, network)

Label: Insurance, infrastructure, configuration, training, support

• Team leadership: Prioritization and coordination of four cross-functional teams.
• Platform strategy: Development and implementation of strategies to optimize existing IT platforms.
• Stakeholder management: Active management of expectations and communication with internal and external stakeholders.
• Program and innovation management: Prioritization and coordination of cross-department projects as well as innovation initiatives.
• Product Owner consulting: Advising Product Owners with a focus on product development and continuous product improvement.
• Organizational development: Improving communication and decision-making structures across all organizational levels.
• Change management: Implementing best-practice change management methods to ensure continuous optimization and innovation.
• Quality assurance: Ensuring high quality standards in processes, services, and deliverables.

• Kubernetes: EKS management, cluster upgrades and stability improvements, Infrastructure-as-Code reviews and updates, AWS support, and cost optimization.

Gronic Ident & Sign

Core technologies: Android, Jetpack Compose, Retrofit, Regula Document Reader, Adobe Sign

Android app on dedicated devices for identifications and electronic signatures at the PoS