PRTG Expert in Germany

Planning and updating the entire environment to Windows Server 2022 and 2025

• Hardening of DCs and servers, setup of event log forwarding
• Migration of all existing Windows 2019 servers (including Active Directory DCs, DNS and CA) to Windows Server 2022 and 2025
• Automation of security patches for the Hyper-V clusters via PowerShell (CAU)
• Network administration
• Continuous operation and support of the MS Hyper-V environments

As a Council Member at GLG (Gerson Lehrman Group), the world’s leading expert network, I provide organizations, investment firms, and consulting companies with expert discussions on demand – wherever specialized knowledge in information security, IT governance, and regulatory compliance is needed.

My assessments are based on many years of practical experience in highly regulated industries: from building and implementing information security management systems (ISMS according to ISO 27001), IT risk and vulnerability management, and business continuity (ISO 22301) to the practical implementation of European regulations such as DORA, NIS2, BAIT, and the Cyber Resilience Act (CRA).

The cooperation is project- and discussion-based. I provide decision-makers with a practical perspective gained from real-world experience on cyber risks, security governance, and operational resilience – exactly when it is needed.

• Management of firewalls (Securepoint)
• Operation and maintenance of the client-server infrastructure (Windows)
• Operation and patching of IoT devices in the hazard management system (cameras, Web IOS, IP-to-serial converters)
• Support with the integration of security technology into existing IT infrastructures
• Planning and implementation of network segmentation and separation
• Transfer and implementation of solutions in other plants
• Tools used: Wireshark, Network Service Manager, PRTG, Cisco Catalyst, Nexus, HP Service, FNT/Command Manager Console, Service Now, Confluence, Active Directory, Wingard, Securepoint FW.

Windows Administrator, software distribution, user support, Azure / Entra Administrator, hardware support, software packaging, defining and introducing processes

Tasks performed:

• Handling incidents, service requests and changes in the Matrix42 ticketing system
• Processing and resolving issues
• User creation / permissions
• Windows installation and patch management
• Entra permissions and license management
• Process optimization and documentation

Tools and methods used: Windows Server 2016 / 2019, Active Directory, Windows 11, Office 365, Azure / Entra, Ivanti, VMWare & ESX, Dell & Kyocera Minolta & Zeus hardware support

Further development of a software solution for managing audit applications and audit notifications according to §106d SGB V for the Association of Statutory Health Insurance Physicians in Hamburg.

• Developed numerous features, optimised performance, refactored code and analysed errors
• Refactored the development container setup
• Optimised the Gitlab-CI build pipeline
• Introduced improvements to the team workflow

Unified ITSM framework

• Definition of a company-wide ITSM target picture
• Introduction of a uniform service structure across all business units

SLA and OLA management

• Building a standardized SLA framework
• Definition of service classes (Business Critical, Standard, Low Priority)
• Introduction of OLAs between internal teams
• Building meaningful SLA reporting
• Definition of KPI and service dashboards for business units

Service portfolio management

• Definition of service descriptions
• If needed, preparing possible cost and service billing

Ticketing & processes

• Incident management
• Uniform ticket categories
• Standardized prioritization
• Escalation matrix
• Automations
• Self-service optimization

Request fulfillment

• Service catalog across all business units
• Approval workflows

Problem management

• Introduction of root cause analysis
• Known error database
• Problem review process

Complete asset management concept

• Hardware lifecycle management
• Software lifecycle management
• Leasing lifecycle
• Mobile device lifecycle
• Monitor lifecycle
• Phone lifecycle

Processes

• Procurement
• Goods receipt
• Inventory
• Assignment
• Return
• Disposal
• Leasing return Goal: single source of truth for all assets

CMDB design

• Definition of all configuration items:
• Workplace
• Notebooks
• Monitors
• Mobile phones
• Printers

Infrastructure

• Servers
• Firewalls
• Switches
• WLAN
• Storage
• Backup systems

Cloud

• Azure resources
• Microsoft 365
• SaaS services

Relationships

• User ↔ Asset
• Asset ↔ Service
• Service ↔ Infrastructure
• Location ↔ Asset
• Goal: make all service dependencies visible

Software asset & license management

• License management concept
• License balancing
• Compliance reporting
• Microsoft license management
• Adobe license management
• SaaS management
• Contract management
• Renewal management

Interfaces & automation Existing systems

• Workday
• Joiner
• Mover
• Leaver

TESMA

• Leasing data
• Contract data

Matrix42

• Asset synchronization
• User synchronization

Active Directory / Entra ID

• User management

Microsoft 365

• License assignment
• Group management

Dormakaba

• Access processes

• Lifecycle services

Monitoring platforms

• PRTG
• Palo Alto
• Cisco

Reporting & KPI framework

• Definition of a management dashboard
• KPIs
• Ticket volume
• SLA fulfillment
• MTTR
• First resolution rate
• Asset accuracy
• License compliance
• Change success rate
• Service availability
• Degree of automation

Network redesign support

• Governance
• Support of the network redesign from an ITSM point of view
• Definition of affected services
• Change management structure
• Communication concept

CMDB integration

• Recording of all network components
• Service mapping
• Dependency analysis

Validation of documentation and knowledge base articles

• Network documentation
• Operations documentation
• Standard changes

Monitoring & event management

• Target picture
• Central monitoring concept
• Event management process
• Alerting strategy
• Escalation model

Systems

• Cisco

• Palo Alto

• Fortinet

• Rubrik

• Veeam

• Matrix42

• Azure

• Microsoft 365 Automation

• Ticket creation from monitoring

• Escalations

• Standard actions

Audit, compliance & information security

• ISO 27001 consulting
• TISAX consulting
• NIS2 preparation - consulting
• Audit-ready processes
• Documentation structure
• Evidence tracking in Matrix42

Roadmap

• 12-month roadmap
• Prioritization of all measures
• Quick wins
• Medium-term projects
• Long-term target picture
• Documentation

• 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.

• Analysis and optimization of the VMware environment for operation in a KRITIS environment
• Planning and implementation of updates to the VMware and hardware environment in a KRITIS environment
• Set up Skyline Health Diagnostics
• Review of the existing documentation
• Training and onboarding of new internal employees
• Support with migration and upgrade projects
• Preparations for moving scripts in the virtualization environment to GitLab
• Ticket processing with Service.Now

• Linux server migrations: Planning and implementation of the migration with SLES Linux Deployment of VMs in VMware 8.0
• Guiding colleagues in configuring Linux VMs in vSphere Auto Deploy
• Application operations: Ensuring the smooth operation of applications on the migrated servers
• Operations manuals: Revising existing operations manuals, adding to them and creating new ones when required
• Reviewing service offerings: Adjusting and optimizing the service offering of external service providers
• Logistics SW, RedHat Linux, Ansible, Confluence / Jira

• Analysis of requirements and the current situation
• Migration of an old domain structure and Tobit to Exchange 2019 with connection to MS365
• Review of implementation options and planning for the protection of sensitive data
• Planning with regard to BSI Grundschutz, BDSG, and DSGVO
• IT governance and IT security backtests
• Support with ERP setup and securing mail transfer
• Hyper-V 2016/2022, Microsoft Terminal Services Cluster, Microsoft Exchange 2019
• Office 365, Microsoft 365, Azure AD, Teams, Salesforce
• Cisco, Zyxel, and HP switches, Sophos firewalls/UTMs, SecurePoint
• Microsoft IIS 2022, IPv4/IPv6, Veeam, Wortmann Online Backup, NextCloud
• Services: DNS, DHCP, TCP/IP, subnetting, firewalling, routing, VoIP, group policies (GPO), SIEM, remote work, home office, high availability, failover, VLAN, PRTG

• Stabilized the cross-site workplace/printer rollout and transferred it into reliable operational processes. Ongoing hospital operations, new naming conventions, new print servers in a different AD structure, Kerberos dependencies, management systems and inconsistent inventory data.
• Took over technical workstreams and escalated risks at an early stage. Interface between IT operations, project organization, internal employees and external service providers; independently responsible for critical technical workstreams without formal overall project management.
• Fully consolidated the central master/rollout data. Correlated serial number, MAC, IP, location and old/new device references from several sources and established them as a shared working basis for rollout, follow-up work, location and toner processes.
• Technically stabilized the printer rollout. 717 devices in the consolidated rollout scope, including 431 replacement devices; 114 documented deviations. Controlled, created or validated around 2,000 printer/queue objects.
• Proposed Location B as an independent work package and managed it technically. Consolidated 216 old devices into 88 new devices; implemented this in around 10 working days with 1-2 external technicians. Prepared ClearPass, TXT/mapping and ORBIS offset topics in parallel.
• Made several thousand existing TXT/VBS client assignments suitable for bulk migration. Defined old/new mapping, new print servers, Follow-Me, queue, suffix and tray logic; developed checking/correction logic for incorrect manual names.
• Built and productively verified cross-domain FollowMe. Used the historical username attribute to map between the old and new AD domains; stopped further expansion when data quality was no longer reliable.
• Developed the technical approach for hardware/queue reconciliation. Correlated standard lists, print server objects and real devices using IP/SNMP; defined rules for MAC, serial number, IP, location, toner, trays, keep/remove/rename, duplicates and rollback.
• Built AI-assisted automation under time pressure. Developed and stabilized PowerShell/XML tools with independently developed process, data and validation logic, test cases, logging, DryRun/guardrail approaches, error analysis and live validation.
• Designed an HTTP/web platform as a target architecture that was not introduced into production. Technically designed ASP.NET Core 8, .NET Worker, SQLite and PowerShell 5.1 for job control, target/actual comparison, logging/audit, recovery, queueing and locking.
• Operationalized toner, location and operational processes. Consolidated TA-Cockpit location data; established toner/order logic with prioritized run lists; supported Follow-Me, duplex and Scan2Mail pilots.
• Worked out the KRITIS/emergency topic in detail. Structured and visualized printer operations during power/infrastructure failures, coordinated internally and supported the integration into the emergency concept.
• Coordinated the workplace/IGEL client rollout with 1.200+ thin clients from a technical and operational perspective. Prepared the project from 11/2025 and continued it from mid-09/2026. Technically reviewed and structured the process from unpacking and labeling/inventory to setup; handed over operational unpacking/label coordination to a colleague so several employees could work in parallel.
• Personally prepared around 120 thin clients for production. Together with a technical colleague, primarily responsible for finding a solution for automated IGEL-OS-12 installation; productive automation is currently still open.
• Saved around 83 hours of manual ClearPass data entry. Created a PowerShell/import script for ClearPass and demonstrably saved the network colleague around 83 hours of manual entry for 1.200 thin clients; at the same time, significantly reduced the risk of manual errors.
• Supplied formal project management with technical results. Operational results, technical feasibility, process structure and status from the responsible workstreams serve as an important basis for steering by the official project manager.
• Documentation & handover. Documented rollout, AQrate, TA-Cockpit and automation processes, conducted training and tested, configured and prepared around 25 digital medical carts for operation.

• Designed and implemented Azure Kubernetes Clusters, and managed DNS and Firewall solutions, enhancing network security and reliability.
• Led projects using Agile Scrum methodologies to streamline development cycles and improve project efficiency.
• Fostered and maintained relationships with suppliers to ensure timely project deliverables and resource availability.
• Managed continuous integration and delivery (CI/CD) pipelines using Jenkins, Sonar, GitHub, Bitbucket, and Terraform within the BMW Azure Cloud environment.
• Utilized Fortify SSC and Contrast AST for robust application security testing.
• Directed DevOps engineering initiatives on the SAP Business Technology Platform (BTP), focusing on streamlining development and deployment processes.
• Service Now governance, risk und compliance (GRC&IRM).

• Freelance product owner, scrum master and agile coach in various projects spanning from local agencies to multinational corporations in diverse industries.

• Last projects:

• Adevinta: Technical Project Manager responsible for coordination of several sub-workstreams building the world’s largest classifieds multi-tenant platform.

• Aroundhome (a ProSiebenSat.1 company): Product Manager implementing and verifying on the business side a concept for digital qualification of user requests for matching service providers.

• Peek & Cloppenburg Düsseldorf: Product Manager Mobile advising on and guiding the rebuild of Android and iOS apps.

• Visual Meta GmbH (an Axel Springer company), Berlin: Director Product co-leading the Product & Engineering department together with the Director Engineering.

• Responsibilities at Visual Meta GmbH:

• Define and deliver a 3–5 year horizon product strategy including a product vision & mission connecting to existing company strategy and strategies from adjacent departments.

• Refine an existing OKR process together with OKR master and directors of other departments to increase focus and outcome.

• Support the Director Engineering in creating a platform transformation strategy to transform a monolithic on-premise tech stack into a service-oriented, cloud-based architecture and establish a domain-based organizational setup.

• Accountability for a motivated and talented team of 5 head-level colleagues and 17 operational team members from product management, data and UX/UI design.

• Key achievements at Visual Meta GmbH:

• Defined and delivered a 3–5 year horizon product strategy including a product vision & mission.

• Increased focus within OKR process by moving from 10 company-level objectives to 2 and from several hundred team-level key results to a few dozen.

• Created a career path framework for the product team defining roles and responsibilities from junior to head level positions.

• Installation, planning, maintenance and further development of the server farm in the area of hardware and software
• Migration of live systems with minimized downtime
• Processing tickets and changes in daily business
• Documentation of changes and processes in Confluence
• Test runs in the development environment
• Configuration and administration of Linux systems
• Configuration and administration of backup systems (Dell Networker, DataDomain)
• Administration of the Checkpoint firewall