Certified Information Systems Security Professional (CISSP)

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

• Developed business strategy, positioning, and market approach for a new B2B and B2C trading company.
• Designed and implemented the corporate website and online shop end to end, and coordinated suppliers and digital sales capabilities.

• 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

• Delivery of various end-customer projects in server and network infrastructure on time, in quality, and within budget.
• Project 1: Firewall renewal, replacement of an ASA firewall with a Fortinet firewall at an automotive supplier.
• Project 2: Migration of file services from dedicated servers at 5 branch locations into a central managed file service, including DHCP, directory, and print services, as well as decommissioning of the old domain controllers.
• Project 3: Renewal of the network infrastructure at the headquarters and branch locations of a logistics company and transition of the LAN, WLAN, and firewall environments into a managed network service.
• Project 4: Network renewal, replacement of the core and access switches at the headquarters of a medical technology company and transition into a managed network service.
• Project 5: Firewall renewal, replacement of an ASA firewall with a Fortinet firewall for a city.
• Environment: ASA and Fortinet firewalls, Cisco network components, ITSM Heat/Ivanti, Confluence.

• Conceptual consulting for securing business processes
• Consulting for planning and implementing IT and IT security projects
• Security and policy checks, process optimization, contingency planning
• Project management and interim management in IT infrastructure and information security

Overview of relevant projects:

• 2025: Consulting on a DLP concept and for Digid GmbH.
• 2025: Consulting for a customer after a cybersecurity attack in which the IT infrastructure was compromised and the attacker gained M365 tenant admin rights. Investigation and recovery of the IT infrastructure. Preparation of recommendations for increasing IT security.
• 2025: Continuation of the projects listed below for Thyssenkrupp Marine Systems and Norddeutsche Landesbank.
• 2024: Preparation of a DNS concept including consulting on DNS strategy and technology, DNS design, DNS security, load balancing, reverse lookup zones and automation. Preparation of a DHCP concept including consulting on DHCP design, the central DHCP management system and automation. Consulting on the operation of the products mentioned, operating processes, and adapting the IT documentation and IT service description for Thyssenkrupp Marine Systems.
• 2024: Analysis and assessment of the network and security infrastructure established by the providers with regard to the overall architecture, consisting of the design and components. Development of proposed solutions to improve current operations, maximize performance and security, and reduce complexity. Presentation of the results, their causes and possible solutions to C-level management, including the required decision templates. Development of a SASE concept based on a Zero Trust architecture for Norddeutsche Landesbank.
• 2024: Continuation of the projects listed below for Atlas GmbH and Deutsche Vermögensberatung AG.
• 2023: Consulting on resolving findings from an IT security assessment of the IT infrastructure, conducting proof-of-concepts for DDoS protection and Digital Experience Monitoring (DEM) with Zscaler (ZIA, ZPA & ZDX), creating a new security architecture based on Zero Trust, redesigning a Cisco ISE implementation and designing a DNS security solution to protect guests and financial advisors for Atlas GmbH / Deutsche Vermögensberatung AG.
• 2023: Continuation of the projects listed below for Digid GmbH, Vaillant Group GmbH (until 09/2023), Bundesanstalt für Geowissenschaften und Rohstoffe (until 05/2023) and Union Investment IT-Services GmbH (until 07/2023).
• 2022: Preparation and review of white papers for infrastructure and security architectures, planning new network infrastructures for Deutsches Luft- und Raumfahrtzentrum.
• 2022: Development of a concept for the technical and process-related modernization of a disaster recovery plan for United Nations Volunteers.
• 2022: Development of a concept for moving measurement data to a cloud environment, introducing Network Access Control and conducting an awareness training session for Digid GmbH.
• 2022: Development of a network segmentation concept for DZ Hyp AG.
• 2022: Development of a network segmentation concept for Bundesagentur für Arbeit.
• 2021: Development of a new load balancer architecture for Bundeswehr Fuhrparkservices GmbH.
• 2021: Vulnerability scan and penetration test of a web frontend, including evaluation and preparation of recommendations for remediation, taking risk and probability of occurrence into account, for customer ifi GmbH.
• 2021: Consulting, concept development and sub-project management for introducing a Network Access Control solution (certificate authentication and MAC address bypass) and macro-segmentation (area and zone concept based on dynamic assignment of endpoints) in office and production IT for customer Vaillant Group GmbH.
• 2021: Upgrade and optimization of the LAN and WLAN infrastructure for customer United Nations Volunteers.
• 2021: Development of a target concept for modernizing the IT security infrastructure consisting of the DMZ (Cisco switches, firewalls, WSA, ESA, SMA), internet access, admin and management networks and wireless LAN, including support during implementation, for Bundesanstalt für Geowissenschaften und Rohstoffe.
• 2021: Creation of a micro-segmentation concept based on Cisco DNA and SGT and Zero Trust for Union Investment IT-Services GmbH.
• 2021: Review and update of ISMS Level-3 policies and preparation of process instructions for customer Software AG.
• 2021: Project management for the global Tec-Refresh project Meraki WLAN 2.0, coordination of outsourcing the LAN/WLAN infrastructure to a managed service provider and preparation of a WLAN concept for automated guided vehicles for customer Heraeus Infosystems GmbH.
• 2021: Project management and technical support for the “Transition of SIEM/SOC Services” project of a customer into a shared environment and assumption of the interim role of Head of Security Operations at customer Datagroup SE.
• 2021: Workshop for a future implementation of Mobile Device Management at customer Allgeier Experts Go GmbH.
• 2021: Sub-project management for introducing a rule management tool for firewalls and recertifying NAC endpoints based on 802.1x and MAB at customer Union Investment IT-Services GmbH.
• 2020: Development of a network segmentation concept for two data centers based on Cisco and VMware for Aareon AG.
• Recording and analysis of the current network architecture, including project initiation.
• Development of a concept for micro-segmentation in the data center and access network.
• 2020: Infrastructure and security architecture audit for customer Stuttgarter Versicherung AG.
• Analysis of the IT infrastructure and IT security architecture with regard to the configuration of network and security components. Additional review of contracts, process descriptions and manuals for completeness. Development of recommendations to improve the stability and operation of the infrastructure. Preparation of a network segmentation concept and project management for implementing the measures from the analysis project.
• 2020: Consulting on setting up an ISMS-Light for customer Josera foodforplanet GmbH & Co. KG.
• 2020: Security architecture consulting for customer Datagroup SE.
• Development of a future IT infrastructure and IT security architecture.
• Analysis of the current IT architecture of all 23 companies.
• Recommendations for optimizing the IT infrastructure and preparation of a comparison between a classic perimeter security concept and the Zero Trust model.
• Preparation of a security zone concept.
• Preparation of an IT infrastructure architecture in coordination with all companies.
• 2018 - 2019: Stream Lead in the Cyber Security program of Deutsche Lufthansa AG.
• Responsible for designing and implementing 9 projects in IT security infrastructure and user access management, as well as managing project managers and experts.
• Project area: Network Segmentation and Access Control.
• Project area: Security Architecture.
• Project area: Privileged, Identity & Access Management.
• Project area: Simplify User Authentication (MFA).
• Project area: Mobile & Endpoint Security.
• Project area: OT Security.
• Project area: E-enabled Aircraft.
• 2018: Security architecture consulting for customer Deutsche Lufthansa AG.
• Project management for the development, evaluation and management of the company-wide information security architecture.
• Development of a security strategy and roadmap to align the security architecture with the Zero Trust model.
• Evaluation of security solutions, services and tools available on the market.
• Definition of requirements for RfPs and evaluation of offers.
• Development, maintenance and monitoring of security architecture artifacts.
• Conducting security assessments of existing and new IT systems and security services.
• 2018: ISMS consulting for customer GLS IT Services GmbH.
• Consulting on introducing and initially operating an ISMS based on ISO27001.
• Auditing the IT environments of the GLS country companies.
• Analysis and assessment of IT security risks and derivation of required measures.
• Development of proposed solutions in coordination with the relevant stakeholders.
• Project management and transition of the ISMS to later operations.
• 2016 - 2018: Security Pre-Sales Consultant for customer Cisco Systems GmbH.
• Nationwide strategic and conceptual consulting for major enterprise customers and financial and insurance customers on Cisco and Meraki security products and services such as Firepower, WSA, ESA, Stealthwatch and ISE.
• 2017 - 2018: Design and implementation of an ISMS for customer Verivox GmbH.
• Conducting various BIAs and GAP analyses.
• Preparation of security policies based on ISO 2700x.
• Assumption of the interim role of Information Security Officer.
• 2017: Preparation of a contingency concept for VPV Lebensversicherungs-AG.
• Review and update of the IT contingency manual.
• 2016: Consulting and project management for the design of cloud and hosting services for customer Vodafone Group Services GmbH.
• Analysis and optimization of the sell-build-run process.
• Preparation of detailed-level designs for cloud products.

• Preparation of a complete IT security concept (ISiKo)
• Implementation of BSI / NATO / national security requirements
• Risk analysis, documentation, audit preparation
• Consulting and management of development teams in Cybersecurity Recovery and Resilience
• Genua firewalls, VPN, VS-NfD migration from Checkpoint and PaloAlto firewalls
• Administration of log sources: firewall traffic, ALG (SIP calls), ATP, DLP
• System administration – servers, AD, clients (according to BSI)
• Stakeholder communication (C-level / government agencies)

• Lead Architecture in an interdisciplinary architecture team covering enterprise, solution, NOOTS, cloud and security architecture as well as regulatory and European interoperability requirements.

• Public / Government

• Development and management of target architectures, principles, standards and technical guardrails; assessment of Security-by-Design, IAM, data protection and interface/integration architectures; architecture reviews, security assessments, risk analyses, and preparation of decision records, target visions, roadmaps and decision papers. Architectural knowledge and consideration of relevant AD-NOOTS requirements, particularly for IAM, authorization, secure integration and interoperability.

• Technologies / Methods: Enterprise Architecture, Solution Architecture, Security Architecture, Cloud Architecture, NOOTS / EU-OOTS, IAM, Authorization, Security-by-Design, API/Integration Architecture, Interoperability, Risk Analysis, Architecture Governance

• Security and integration requirements as well as technical decisions are structured in reliable architecture and decision artifacts.

I implemented a Zero-Trust architecture for robust, military-grade maritime container mini data centers based on VMware & Tanzu to support containerized GIS workloads for ground forces. The main focus was on securing communications, workload protection, and data access in contested electronic battle environments affected by jamming, interception, signal manipulation, and constantly changing operational conditions. I designed and architected use cases so that every element of workload, identity, and system could continue to operate independently and securely even in degraded or disrupted scenarios. In parallel, I defined the enterprise and solution security architecture with LeanIX, Bizzdesign, and HOPEX as enterprise architecture, repository, and governance platforms to maintain architecture inventory, relationships, traceability, target pictures, and security governance in complex environments. For the architectural designs, I used Sparx Enterprise Architect to describe formal architecture views, interfaces, trust boundaries, and system architecture in both IT and OT environments. IriusRisk was used for threat modeling of the solution to identify architecture-driven risks, derive security requirements, and detect countermeasures and design gaps directly from the solution models. Risk and compliance management was supported with Archer. Architecture decisions, control gaps, and operational risks were translated into controlled governance and auditable compliance measures. For documentation, collaboration, and visual design, I used Confluence to maintain Architecture Decision Records, Security Blueprints, and workflows. I used Lucidchart and draw.io to create design artifacts tailored to stakeholders. I also defined OT security concepts with support from electrical and mechanical engineers in the areas of oil, vehicle onboard systems, rail, power plants, pharma, gas turbines, and nuclear technology. I created the end-to-end OT security strategy, starting with global policy, developed into standards and procedures, and finally aligned with Bell-LaPadula, Purdue Model, SABSA, TOGAF ADM, CENELEC 50701, IEC 62443, and NIST standards. In addition, I worked with engineering team leads to identify critical KBP assets and place them under protective measures that segmented SCADA, PLC, and HMI assets. I drove collaboration between Security, IT, and OT teams to create standardized workflows and use cases for the OT security solution catalog, while integrating Defense-in-Depth and Zero-Trust principles into operational environments. A key part of my work was integrating multidisciplinary engineering, security, and operations stakeholders into a unified security blueprinting strategy and ensuring that architecture, threat modeling, governance, and documentation were technically strong and operationally practical.

• Sole responsibility for the management and strategic direction of an IT services and consulting company
• Responsible for company development, business development and market positioning
• Development and implementation of corporate strategies, business models and processes
• Contact person for customers, partners and stakeholders

• Supported the implementation of §8a requirements of the BSI Act for critical infrastructures.
• Systematically prepared and supported internal and external audits, resolving previous deviations (HA, NA, VP)
• Implemented the specific requirements of the IT security catalog
• Developed training, created run books, and conducted assessments to ensure operational effectiveness.

• Worked on FPGA enhanced network encryption device with secure boot, TPM2.0 and smart card integration for BSI approved usage with Post Quantum Cryptography
• Developed and audited Linux drivers
• Collaborated using GitLab, Gerrit, Confluence and Jira
• Technologies: C, C++, Secure Boot

• Recognition of national notified bodies
• Preparation of cybersecurity competency reports
• EU Radio Equipment Directive

• Development of comprehensive services in cybersecurity, IT governance, and AI
• Building and delivering strategic security solutions such as vCISO service, ISMS, SOC-as-a-Service (SIEM, SOAR, use cases, playbooks, threat hunting, incident response), AI-driven risk and compliance tools, and frameworks for outsourcing and third-party risks
• Supporting companies in meeting regulatory requirements and certifications (ISMS, NIS-2, DORA, CRA, KRITIS, ISO 27001, TISAX, BSI IT Baseline Protection, EU AI Act)
• Promoting innovations in cybersecurity automation, AI governance, and secure digital transformation
• Responsible for company growth, client relations, and strategic partnerships

• Analyzed the required scope of processes, infrastructure, and SAP for integrating the MacDermid subsidiaries
• Validated proposals from the new service providers
• Managed the collaboration and tracked the tasks of business and IT experts
• Coordinated communication and the PMO
• Created cutover plans in three waves for SAP conversion, Salesforce, and Ariba