Security Operations · Network Defense

John K. DeMarzo

Cybersecurity graduate moving from time-critical public-safety operations into security operations — bringing incident triage, escalation, and after-action discipline to a hands-on lab practice.

Targeting SOC Analyst / Detection & Identity roles — Austin–San Antonio or remote. Available now — graduated UTSA, August 2026.

New Braunfels, TX

Summary

Cybersecurity graduate and CompTIA Security+, CySA+, Network+, and PenTest+ certified professional transitioning from public-safety operations to security operations. Hands-on lab work spans network segmentation, packet and alert review, cloud honeypot monitoring, and Linux/Windows infrastructure.

Brings structured incident triage, escalation, documentation, and after-action review experience from time-critical emergency response.

Security monitoring experience is lab-based, not commercial SOC employment.

Also open to systems / network administration roles.

Certifications & Education

  • CompTIA Security+SY0-701
  • CompTIA CySA+ ceCS0-003
  • CompTIA PenTest+ cePT0-003
  • CompTIA Network+ ce
  • Google Cybersecurity Professional Certificate2024
  • AWS Cloud Support Associate Professional Certificate2024
  • CISA 100W ICS Cybersecurity Practices2026

BBA, Cybersecurity

Aug 2026
The University of Texas at San Antonio · GPA 3.84

AS, Computer Information Systems

Aug 2024
San Antonio College

Technical Skills

Security operations & monitoring

Splunk and Wazuh local deployments; Snort alert review; Zeek, Suricata, tshark, Wireshark; SANS Internet Storm Center log review; DShield and Cowrie honeypots; Nmap.

Network defense & infrastructure

Seven-VLAN segmentation; TP-Link Omada SDN; firewall access rules; OPNsense and UFW lab configuration; DHCP/DNS; Proxmox VE; AWS EC2 and security groups.

Systems & methods

RHEL, Ubuntu, Windows 10/11; Bash; Ansible lab playbooks; NIST and SANS incident-response guidance; MITRE ATT&CK; technical reporting.

OT/ICS lab exposure

Modbus/TCP, DNP3, OPC UA, BACnet; PLC/RTU register reads; IT/OT segmentation and zone-and-conduit concepts.

Projects & Security Labs

Cloud Honeypot Deployment & Security Monitoring

Spring 2025
UTSA coursework
  • Deployed Ubuntu Server 22.04 in AWS EC2 with DShield and Cowrie sensors; validated service status, log paths, firewall rules, and reporting workflows to collect security observations.
  • Restricted administrative SSH to one approved source IP and a nondefault port using AWS security groups; reviewed firewall and web-log submissions through the SANS Internet Storm Center and documented scanning observations.
Independent · GitHub repo
  • Segmented a seven-VLAN Proxmox environment with Splunk as the SIEM — Sysmon, Windows, DNS, and firewall log onboarding — plus an isolated attack VLAN with Linux targets, to run the full SOC loop: emulate, detect, investigate, document.
  • Verified default-deny firewall isolation between VLANs with before/after testing; documented architecture, design decisions, and SPL detections as code.

Status: infrastructure, SIEM, and lab isolation are built and tested; first attack-to-case write-ups in progress.

Independent · GitHub repo
  • Built a hybrid identity lab on an isolated Proxmox software-defined network: on-premises Active Directory synced to Microsoft Entra ID, with staff signing in as @demarzo.dev.
  • Scoped for Microsoft SC-300 exam coverage — Conditional Access, MFA, Identity Protection, PIM, and identity governance — with network isolation verified before identity work begins.

Status: network layer in progress; identity and governance labs planned next.

OT/ICS Network Security & Protocol Analysis

Summer 2026
UTSA coursework
  • Reviewed Zeek, Suricata, tshark, and Grafana evidence for reconnaissance and anomalous industrial-protocol activity in controlled lab environments; documented Modbus/TCP state changes, process restoration, and mitigation priorities.

Professional Experience

  1. Texas State University — ALERRT Program

    Feb 2017 – Dec 2024
    Contract Instructor / Lead Instructor / Subject Matter Expert

    National active-attack integrated-response training program serving multidisciplinary public-safety audiences.

    • Delivered repeatable response training for classes typically ranging from 15–30 participants by facilitating scenario-based exercises and adapting instruction to operational and safety requirements.
    • Coordinated instructor teams on approximately 40% of assignments as Lead Instructor; developed and delivered 20+ scenario-based exercises and incorporated performance feedback into course delivery.
  2. Bexar County ESD #12 Fire / Rescue

    Sep 2019 – Aug 2023
    Engineer / Lieutenant / Acting Captain

    Fire/rescue agency providing time-critical emergency response, multi-station readiness, and mutual-aid operations.

    • Directed response and resource prioritization across two stations as Acting Captain, coordinating 5–7 personnel and 7–9 apparatus by applying incident command and clear operational communications.
    • Improved inspection visibility for PPE assigned to 40+ personnel by administering PS Trax checks and accountability workflows; reviewed incident records and facilitated after-action reviews to inform procedures.
  3. Hays County ESD #3 — South Hays Fire

    Oct 2011 – Jun 2022
    Training Captain / EMT

    Combination fire/rescue organization supporting response, training, personnel readiness, and mutual aid.

    • Increased training attendance, hands-on engagement, and learner retention by 150% over one year, measured through participant counts and retention surveys, by introducing blended onboarding and structured mentoring.
    • Supported classes of 15–30 and up to 80 members through Moodle, Pearson, IFSTA, and FireRescue1 training workflows; documented plans, SOPs, and operational reports.

Additional Experience

  • JM Electronic Engineering, Inc. — Senior Service Technician / Installation SupervisorMay 2012 – Sep 2017
    Programmed, tested, and troubleshot commercial fire-alarm systems and IP/cellular monitoring links.
  • Texas Fire Academy — Lead Fire Instructor / EMS InstructorJan 2013 – May 2021
    Delivered practical training and documented after-action findings.
  • Massachusetts Army National Guard — Cannon Crewmember (13B), Specialist (E-4)Feb 2001 – Dec 2007
    Planned and reviewed time-sensitive security-detail missions; honorable discharge.
  • 1 Beyond, Inc. — Systems Engineer / Tech Support LeadNov 2002 – Jun 2004
    Configured mobile workstations and troubleshot client systems on location.

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