Juniper Networks Experts in Germany

• As-is assessment of the current network infrastructure and its documentation, including on-site inspections
• Independent planning of new distribution and main distribution rooms in the individual district offices (components used, rack layout, connectivity), considering the BSI IT-Grundschutz and InfoSic requirements
• Planning of new copper and fiber optic cabling, including patch panels
• Coordination with building services engineering (TGA) to ensure compliance with relevant on-site requirements
• Development of detailed execution plans and high-level concepts for the rollout of the new infrastructure
• Additional support after the components go live (hypercare phase)
• Regular communication with project management and client stakeholders

• Optimization of the transmission media of the data links in the Ruhr area
• Configuration/expansion of switches and routers for an autonomous system AS
• Improve the network protocols used Layer 2/3 (OSI model), RSTP, broadcast, etc.
• Laying cables, crimping, antennas, routers, switches
• Maintenance, expansion, selection and prioritization of troubleshooting measures for network monitoring (PRTG, The Dude)
• Organization and new connection of another BGP peering, data center, NGN fiber optic
• VPN IPSec site connections for 6 sites with PFSense, Fritzbox
• Configuration of WLAN devices (Mikrotik, UBNT

Label: TCP/IP, VLAN, BGP, OSPF, MPLS, VPLS, routing protocols, WLAN, EoIP, PPPoE, routing, SNMP, DHCP, DNS, NAT, native IP, VLAN, Ethernet, VoIP., switches and routers from: Nortel, Cisco, MikroTik, UBNT., network management systems: The Dude, PRTG, UISP

• Idea, design and initial implementation of a service that aggregates publicly available data to estimate prices for certain types of objects
• Collection of data from different data sources and its normalization. Embedding the data using SentenceTransformer and training gradient boost models
• Implementation of a web service that
• reads arbitrary user text
• extends it if some parts of data are missing
• uses a local LLM model to prepare the data for prediction
• embed the data and call for prediction from the gradient boost model
• uses a LLM model to generate a report for the user request including explanations
• Stack: BigQuery, Vertex AI, Cloud Run (GCP), Python, Terraform, DBT, SentenceTransformer, Qwen
• Minor SEO optimizations
• More to come...

Participation in various projects related to the development and introduction of new telecommunications products in the mobile communications and fixed-line sectors, with a focus on 5G, wholesale and IPv6 technologies.

• Planning, coordination and execution of product development projects, particularly in the 5G and fixed-line environments
• Support for the rollout of new offerings, including test management and quality assurance
• Participation in the development of wholesale products and eSIM solutions
• Close coordination with internal departments (technology, marketing, operations) and external partners
• Use of agile tools and methods for project management and collaboration

Tools: JIRA, MS Office, MS Project

Technologies: 5G, 5G Campus Networks, Fixed Network (FixNet), IPv6, eSIM, Wholesale product development

CS-APN 5G NSA – IPv6 / Dual-Stack for B2B Customers

Ensuring the use of CS-APNs in dual-stack mode (IPv4/IPv6) in combination with MPLS VPN and IPSEC VPN.

• Project management including test planning, test coordination and go-live management
• Technical coordination for activating IPv6 functionality for B2B connections

eSIM Manager – Product Development for B2B Customers

Development of a tool for the fast and scalable provision of eSIM profiles for business customers.

• Product design and process definition for activating eSIMs on different device types (smartphones, IoT, laptops)
• Collaboration with partners to integrate the solution into existing infrastructures

eSIM Handling B2B – Blanco eSIM Process Integration

Optimization of the eSIM provisioning process through the introduction of dynamic Blanco eSIM processes.

• Definition of new processes for issuing non-activated eSIMs (Blanco) via the frontend and partner community
• Design of the integration into service and IT systems

All-IP 5G NSA – Mobile Access for B2B Internet/Voice Services

Expansion of the All-IP portfolio with mobile 5G access offering higher bandwidth for business customers. (5G Indoor Coverage).

• Project management including test management and go-live preparation
• Interface coordination for introducing Local-SIM-based solutions

5G PN – Campus Roaming / Private Networks

Development and introduction of 5G Private Network (PN) solutions with a focus on industrial applications (IIoT).

• Design and definition of business use cases
• Development of SIM/eSIM processes for 5GPN, including roaming between private and public networks

IPv6 for B2B – Introduction in Mobile and Fixed-Line Products

Introduction of IPv6 support for All-IP products and M2M services in the B2B environment.

• Product and process development for integrating IPv6 (in accordance with RIPE-554)
• Implementation for large customers such as retail chains with several thousand branches in Germany and abroad

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.

• The customer is undergoing a comprehensive transformation. All SAP ECC landscapes worldwide are being migrated to SAP S/4HANA, with the goal of introducing a standard template worldwide.

• The program also includes the “RISE with SAP” migration and modernization program, which may involve migrating the landscapes of selected country installations to the SAP Private Cloud.

• On the stakeholder side, the program reporting line extends to the company’s executive board and that of the implementation partner.

• Fiserv Germany’s ERP landscape currently includes several non-standard SAP tools and applications that extend the functionality of the ECC environment and can often be integrated into downstream systems. As part of the transition to SAP S/4HANA, it is essential to assess the core functionality, integration points and future viability of these applications in order to determine their alignment with the target architecture.

• The focus of the work is on providing expert advice and assessment to define the scope, strategy and roadmap for transitioning Fiserv Germany’s SAP ECC system to SAP S/4HANA.

• The recommended best practices from SAP are followed and a structured approach is used to ensure a smooth transition with minimal disruption while maximizing business value.

• This assessment forms the basis for a successful SAP S/4HANA transformation and ensures alignment with industry best practices, regulatory compliance and future scalability.

• Migration Strategy Definition – assessment of available transition approaches based on business objectives, technical feasibility and SAP Best Practices.

• Technical Readiness Assessment – conducting a system analysis to assess compatibility, custom code impact, data volume management, integration points and infrastructure readiness for SAP S/4HANA.

• Business Process Impact Analysis – reviewing the latest business process documentation to define the scope and effort required to implement the necessary functions in SAP S/4HANA and to identify opportunities for process optimization.

• Roadmap for Non-SAP Systems and Applications – assessment of third-party and legacy applications regarding their integration with SAP S/4HANA and recommendation of consolidation, migration or replacement strategies.

• Deployment & Implementation Planning – defining a phased approach for implementation, including project schedules, risk mitigation strategies and key milestones aligned with business priorities.

• This transformation takes place in phases: the Discovery phase leads to the Explore phase, which is followed by the Design phase and finally implementation.

• Program management

• Change management

• Requirements management

• Transition management

• Stakeholder management

• Risk management

• Comprehensive coordination

• Specialized in designing and implementing robust, secure cloud solutions for critical client infrastructure.
• Expertise in Microsoft Intune environment with a strong focus on system hardening and comprehensive policy management.
• Architected NIST and ISO/IEC 27000 compliant Mobile Device Management (MDM) infrastructure tailored for an international government defense aerospace project.
• Performed an architectural role for an offline Microsoft Endpoint Configuration Manager (MECM) environment, ensuring NIST compliance while handling complex manufacturing infrastructure.

• Designed a network management strategy focused on NetDevOps principles and model-driven telemetry using YANG data models
• Conducted NETCONF/YANG workshops for L2VPN/L3VPN services over SRv6
• Automated configuration deployment in the testing environment with Ansible
• Developed end-to-end service measurement concepts with IPSLA and the Telegraf-Prometheus-Grafana stack
• Created the dual-stack architecture design (router + switch + firewall) including a detailed test plan; planned, executed, and documented acceptance tests for the management network
• Performed BSI IT baseline protection checks according to the IT-Grundschutz catalog (needs assessment, modeling, risk analysis, deriving measures)
• Protocols: SRv6, IPv6, MPLS, BGP, ISIS, OSPF, NETCONF/YANG, model-driven telemetry, IPSLA
• Systems: Cisco Crosswork Network Controller, SolarWinds Orion, Grafana, InfluxDB, Telegraf, Ansible, Git
• Components: Cisco NCS router series, Cisco Catalyst switch series, Cisco Firepower firewall series

• Manage the development release and update process for a digitized nationwide trade register project "AuRegis".

• Support software in Kubernetes/OpenShift environments, configure management with Kustomize, and implement CI/CD pipelines using Jenkins/GitLab, SonarQube, ArgoCD, and Azure.

• Oversee system release of microservice architecture.

• Build the CI/CD stack from scratch with GitLab CI, integrating integration tests, dependency checks, and security measures.

• Automate deployment onto OpenShift using Kustomize.

• Set up infrastructure components for development, code review, and code quality analysis including SonarQube.

• Integrate GitOps tools such as Kustomize and ArgoCD, using both Azure and private cloud for sensitive data handling.

• Develop Python scripts in Jenkins for cryptostore configuration and system packaging of products and microservices into deployable units.

• Automate delivery to customers and deployment on test systems.

• Create Kustomize manifests for microservices and develop the related automation, treating documentation as code for clarity and reproducibility.

• Serve as technical advisor for the project's first go-live and oversee further deployments as technical rollout manager.

• Designed and specified the technical network integration of a new business-critical application system (MUREX) in the capital markets area in a complex interface and outsourcing environment.

• Created component specifications, a catalog of measures and an implementation plan.

• Ensured proper integration of the developed results in line with the bank’s framework: IT compliance, IT security, change and release management.

• Selected and integrated a new service provider for the bank; moved critical bank applications to the provider.

• Designed, implemented and supported the new Cisco network and Fortinet security setup at the service provider data center.

• Acted as technical interface between the bank, service providers and consulting partners.

• Supported and further developed the network and security infrastructure (clients, servers, networks); performed error analysis and implemented solutions within agreed service levels.

• Analyzed and diagnosed all security and network failures, glitches and malfunctions.

• Initiated continuous improvements to ensure efficient resource use and acceptable response times for users.

• Provided network support in a financial services organization and prepared operational changes on production banking network infrastructure for both large and small projects within strict change management discipline.

• Designed, defined, tested, governed and improved engineering standards.

• Performed the role of network architect for medium to large projects involving team resources.

• Operation, maintenance and administration of the global network & security system landscape
• Troubleshooting and support in 2nd & 3rd levels and provide technical advice to other dept.
• Configuration of complex LAN/WAN/SD-WAN and WLAN network infrastructures (N5K, N9K, ASR 8000, Wireless Controller WLC9800, AP C91xx and VMware Velo Cloud)
• Control of external service providers as part of service and escalation management
• Implementation and monitoring of system updates (software upgrades, minor/major changes)

• Responsible for the configuration, maintenance, monitoring, troubleshooting, and optimization of the IT infrastructure, including Extreme Networks, SD-WAN, and Fortinet security solutions, at all international company locations in Europe and North America
• Development of a comprehensive strategic roadmap to optimize the network architecture, including VLANS, NAC, QoS, firewall configurations, VPNs, DPI, NGFW, threat intelligence, and SSL/TLS inspection
• Implementation of the OneIT strategy through the introduction of new technologies such as Cisco DNA Center, ExtremeCloud IQ, FortiOS, FortiManager, and FortiAnalyzer, which increased employee skills and the efficiency of the IT systems
• Integration of IT and OT systems to optimize the network and security architecture and improve operational efficiency

• 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.

• Network automation
• CI/CD and Docker environment
• Python Nornir for network automation
• pyATS for monitoring and test case automation
• Network Access Control (Radius) and Device Admin Access Control (TACACS) with AAA and Cisco ISE with Cisco/HP/Aruba Devices
• Cisco ISE Clusters (2/4/8 nodes) configuration
• Cisco ISE Authentication and Authorization configuration
• Cisco/HP/Aruba Switch/WLC Tacacs/dot1x/Radius configuration
• Cisco ISE automation with Restconf and Python