Cybersecurity · Enterprise Infrastructure · Network Automation · Cryptography · Telecom · HF Communications
Senior IT Engineer · Miami, FL
Comprehensive VMware ESXi hardening guide covering 45 security controls — lockdown mode, firewall, account management, audit logging, SSL/TLS, and service hardening.
Practitioner's overview of VMware vSphere 7 security configuration — authentication, permissions, encryption, network hardening, and compliance alignment.
Real-time IPMI-based CPU temperature alerting for VMware ESXi hosts — Python implementation, threshold alerting, and integration guidance.
Production rewrite of a PowerCLI ESXi shutdown script — code review methodology, error handling, graceful VM shutdown sequencing, and vCenter integration.
Step-by-step ESXi recovery using hostd, localcli, vim-cmd, and log triage — covers management agent restarts, host unresponsiveness, and diagnostic procedures.
Enterprise VMware infrastructure architecture — vSphere stack layers, cluster design, vCenter topology, storage, networking, and HA/DRS configuration.
Security hardening guidelines for VMware SD-WAN VeloCloud — edge hardening, orchestrator access control, tunnel encryption, and security policy design.
Converting Cisco CSR1000v serial consoles into a programmatic REST API — socat transport bridge, Flask gateway, authentication, and Cloudflare Zero Trust tunnel integration.
Full technical report on the Flask/NAPALM/Netmiko programmatic gateway over Cisco CSR1000v. Architecture, API design, Cloudflare Zero Trust tunnel, Tailscale WireGuard mesh.
Disabling Cisco Call Home and controlling outbound device communications — IOS-XE configuration, Smart Call Home, Phone Home suppression, and audit verification.
Troubleshooting guide for Nexus 1000V port channels and trunking — vEthernet port profiles, VEM configuration, CDP, and common failure modes.
Full architecture diagram for the Flask/Netmiko/NAPALM gateway — component layers, API flow, Cloudflare tunnel, Tailscale mesh, and connectivity overview.
Expansion roadmap for the automation stack — NetworkX topology engine, Nornir parallel execution, Scapy packet analysis, Nginx SSL, and priority implementation sequence.
Complete SD-WAN lab for GNS3/EVE-NG — topology diagram, dual-transport IP addressing, OSPF underlay, vManage templates, and WAN failover testing.
Complete integration guide — 12 undocumented bugs with root causes and confirmed fixes: chan_sip removal, Asterisk 22 AMI format changes, MySQL 8.4 breaking changes, Docker RTP port mismatches.
Full SS7 protocol reference — out-of-band signaling architecture, SSP/STP/SCP roles, ISUP call setup sequence, TCAP transaction capabilities, MTP link types, and protocol layers.
Mathematical foundations of AES — GF(2⁸) field construction, irreducible polynomial selection, multiplicative inverse via Extended Euclidean Algorithm, and SubBytes derivation.
Condensed mathematical reference for GF(2⁸) operations used in AES — field arithmetic, S-Box construction tables, MixColumns polynomial, and implementation notes.
Integer factorization pipeline — trial division, Pollard's Rho, Lenstra ECM, Quadratic Sieve, and General Number Field Sieve. Algorithm selection thresholds and Python implementations.
Deep-dive into the Quadratic Sieve algorithm — smooth number sieving, factor base construction, Gaussian elimination over GF(2), and LPQS pipeline implementation.
Analysis of energy-efficient strategies for General Number Field Sieve — polynomial selection impact, sieving region optimization, CADO-NFS configuration, and computational cost modelling.
Technical comparison of IBM PowerHA geographic mirroring and journal-based replication — RPO/RTO trade-offs, infrastructure requirements, failover behaviour, and selection criteria.
CIA triad, risk management, access control models, cryptographic principles, and compliance frameworks — structured reference for security practitioners.
Domain controllers, FSMO roles, replication topology, DNS integration, Group Policy, trust relationships, and operational best practices.
Network isolation analysis of a Bitcoin full node running inside an LXD sandbox — traffic inspection, firewall rules, peer connection behaviour, and security posture.
Technical report covering full macOS system restore using Target Disk Mode — procedure, commands, edge cases, and lessons learned from a production restore.
Flask API gateway for Cisco CSR1000v fleet management with Cloudflare Zero Trust and Tailscale WireGuard mesh.
Integer factorization algorithms (QS, GNFS, Pollard, LPQS), AES large-file encryptor, and number theory references.
OWASP Top 10 laptop file and code scanner — pattern engine for A01–A10, live filesystem watcher, and 4 online signature databases: CIRCL, MalwareBazaar, VirusTotal, NIST NVD.
Security tooling — OSSEC log monitoring, SSH hardening, Tor service management, and vulnerability auditing.
Python serial interface for Harris modems, Fortran signal processing wrappers, STANAG waveform analysis tools.
Cisco SD-WAN lab — GNS3/EVE-NG topology, OSPF underlay, vManage templates, and WAN failover testing.
IPv6-to-MAC lookup, network diagnostics, and session management utilities for enterprise environments.
Audio and image signal processing — frequency analysis, spectrogram generation, waveform inspection.
FastAPI-based AI integration platform with LLM tooling and Docker containerisation.
Google Earth Engine scripts for elevation analysis and environmental monitoring.
Market dashboard with yfinance and Alpha Vantage — real-time price tracking and portfolio monitoring.
BigQuery and SQLite utilities for data management and analytics automation.
Source repository for all 24 published technical articles across VMware, Cisco, cryptography, IBM i, telecom, and HF radio.
Real-time BTC/ETH/LTC/TRUMP price trackers using the Coinbase API — terminal UI with color-coded price changes.
Educational build log: 10-VM carrier telecom stack — Kamailio, Asterisk, A2Billing, MariaDB, OSSEC, and Zabbix on isolated virtual networks.
Pulse In Time Tunes Agency — Music Beyond the Ordinary.
Professional biography — Ioannis Alexander Konstas. Cybersecurity, enterprise infrastructure, cryptography, and network automation.