Architecting the Connected Future
Certified Network Associate (CCNA) specializing in Cisco Networking, Azure Administration, Windows and Microsoft 365 Solutions.
About Me
About Me
Hello! I am Oscar Sefa Mireku, a Network & Systems Professional and a Cisco Certified Network Associate (CCNA).
I am a results-driven IT professional specializing in the design, deployment, and management of secure enterprise infrastructure. As a graduate of the NBCC IT Network Administration program and a Cisco Certified Network Associate (CCNA), I bridge the gap between complex network engineering and user-focused technical support.
My approach combines a deep understanding of Cisco-based networking with a proficiency in Microsoft 365 and Hybrid Cloud environments. I don't just study technology—I build it. From maintaining a robust physical homelab with enterprise HPE servers to automating tasks with PowerShell, I am constantly refining the skills needed to keep modern businesses connected and secure.
Core Expertise
- Networking: Configuring and troubleshooting Cisco Routers & Switches (VLANs, ACLs, OSPF, STP), and Network Security.
- Systems & Identity: Administering Windows Server, Active Directory (GPOs, DNS, DHCP), and Microsoft Entra ID.
- Cloud & Virtualization: Supporting Microsoft 365/Exchange environments and managing VMware ESXi/Azure hybrid infrastructures.
- Technical Support: Delivering high-tier troubleshooting and service desk excellence with a focus on minimal downtime and user satisfaction.
Why I Do What I Do
Beyond the command line, I am a problem solver at heart. Whether I’m architecting a
high-availability domain controller or helping a user navigate a critical system
failure, I am driven by technical curiosity and a commitment to reliability. When I’m
not at my desk, you’ll likely find me on the road or exploring music—interests that keep
my perspective fresh and my creativity fueled.
Core Competencies
Certifications
Azure Administrator Associate
Microsoft
Incoming: March 2026
Professional Experience
IT Technical Support - Intern
Arauco North America, Canada
- Configured, deployed, and maintained Windows-based PCs and laptops
- Documented and updated system configurations and procedures.
- Provided support and troubleshooting of Microsoft 365 applications including Outlook, Word, Excel, and Teams.
- Assisted with the installation and configuration of software and hardware.
IT Support Assistant
Challenge Solutions, Ghana
- Monitored network activity and conducted routine system checks to ensure optimal performance and security.
- Performed hardware diagnostics, pc and printer repairs, and device setups, contributing to a 15% improvement in system uptime.
- Assisted in configuring and deploying cisco routers and switches for small office environments.
- Delivered technical support to end-users, resolved common IT issues, and documented service requests with Spiceworks.
Technical Proficiency
Network Engineering
- Cisco IOS & CLI
- Switching & Routing (VLANs, STP)
- Routing Protocols (OSPF,EIGRP)
- Network Monitoring & Analysis
Cloud & Systems
- Microsoft Azure & Entra ID
- Windows Server 2019/2022
- Active Directory Domain Services
- VMware vSphere & ESXi
Security & Ops
- Network Security & ACLs
- Firewall Configuration
- Troubleshooting & Diagnostics
- System Automation (Ansible)
Featured Projects
Enterprise Virtualization with VMware ESXi
Deploy and configure VMware ESXi for enterprise virtualization
SSPR Setup in Entra ID
Implement a Self-Service Password Reset (SSPR) solution in Entra ID
DHCP Deployment with Custom VNet in VMware
Implement a hybrid lab environment with centralized Windows Server DHCP integration across VMware Custom VNets.
Hybrid Identity with Microsoft Entra ID Connect
Configure Entra ID Connect to sync On-Prem users to Entra ID
Let's Connect
Interested in collaborating on a project or discussing network architecture? Drop me a message.