- Design, implement, operate, and maintain enterprise PKI and cryptographic security infrastructure across on‑premises and cloud environments.
- Perform day‑to‑day PKI operations, including certificate lifecycle management, key management, platform maintenance, and infrastructure upgrades.
- Monitor cryptographic platforms and security posture using tools such as Splunk, identifying vulnerabilities, misconfigurations, and anomalous activity.
- Coordinate vulnerability remediation and risk reduction activities in collaboration with engineering and operations teams.
- Implement and maintain cryptographic solutions, security device policies, and PKI service configurations.
- Troubleshoot and provide global technical support for PKI infrastructure across multiple regions.
Greg Tumminia
Systems Engineer
Computer Engineer
Cyber Security
Greg Tumminia
Systems Engineer
Computer Engineer
Cyber Security
About Me
Dedicated and results-driven IT professional with 6 years of experience in Technical Support, Data center System maintenance with a proven track record of projects successfully completed involving leading IT infrastructure upgrades, remediate vulnerabilities and resolved complex IT issues.
Passionate about emerging technologies, cybersecurity and networking, I thrive in dynamic environments where I can leverage my technical skills to solve complex challenges and drive innovation. My strong communication and problem-solving abilities enable me to collaborate effectively with cross-functional teams and deliver solutions that meet both technical requirements and business objectives.
With a commitment to continuous learning and staying updated with the latest advancements in technology, I am eager to contribute to the overall success of IT organizations.
Certifications
Contact me
Resume
Experience
2025 - Present
Cryptography Infrastructure Engineer
, Cybersecurity Operations
Dell Technologies
2021 - 2025
Senior Engineer, System Maintenance
Dell Technologies
- Mentoring new hires, system logs and system maintenance plan validation
- Handling EMEA Datacenter escalation and resolve complex issues
- Review vendor releases, security patches, and software updates related to the system.
- Analyze system logs to maintain: Servers, Chassis, blades, switches, compellent and storages
- Apply updates as needed, considering their impact on system stability and compatibility with other components and vulnerability remediation.
- Troubleshooting environment and/or system issues during delivery before escalating to relevant Support teams
2020 - 2021
Technical Enterprise Tier 2 Support EMEA & AMR
Apple
- Providing technical hardware and software support for business and education users
- Responsible for establish and dispatch hardware parts required for onsite service repairs
- Identifying bugs, emerging issues and/or complex technical issues in order to find resolution and to provide product technical feedback
- Providing Server and Deployment Support DEP and MDM solutions
2019 - 2020
IT Client Service Desk Support EMEA
SAP
- Provide application support for both Internal and External SAP employees
- Deal with all the incoming IT support tickets and ensure resolution in adherence to the agreed SLA
- Good working relationships with end-users and excellent communication with stakeholders to seek constant improvement
- Apply solutions, workarounds, patches and fixes as defined in SAP Knowledge Base
- Highlight all potential major IT incidents and problems to the respective service and problem managers
- Ensure compliance with all security standards and policies
- Provide new agents Training and tools necessary to improve operations and promote consistency
2019
HelpDesk
ALLIANZ CARE
- Provide technical assistance and support to colleagues as required
- Installation & configuration of a company’s computer hardware operating systems and applications.
- Logging the queries of customers and employees.
- Diagnosing and solving hardware or software faults Maintenance and monitoring of computer networks and systems
- Daily use of Microsoft Office (Excel, Word) Outlook and Salesforce.
2016 to 2019
Technical Account Manager
Amazon
- Provide a prompt and efficient service to Amazon Sellers and Merchants including the appropriate escalation of Seller’s issue
- Demonstrate excellent time-management skills and the ability to work independently
- Provide outstanding performance metrics such as quality, productivity, first contact resolution
- Escalate issues with other departments such as Customer Service, Merchant Investigations or Payments teams
- Manage Amazon inventory and FBA shipment including planning/shipping/reconciliation/reporting
- Responsible to approve high value reimbursements
Skills
Cloud
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Vmware VSphere
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Microsoft Hyper V
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Microsoft Azure
Networking
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OSI Model
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Types of Network Topology
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DSN, HTTPS, TCP, UDP, LDAP, FTP
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LAN, WAN, MAN, CAN, PAN
System
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Linux82%
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Microsoft90%
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ESXI85%
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macOS80%
Knowledge
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Managing and Maintaining Servers, routers, firewall, switches
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Knowledge of TCP, UDP, DNS, DHCP, HTTP, SSH, TFTP, FTP, and other common core internet technologies and services.
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Packet captures using Wireshark
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Knowledge of NAS, SAN and Raid Levels
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Linux and Windows management
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Network security