Senior Network Engineer III — Infrastructure & Security

JMARK - IT Support and IT Services; Tulsa (OK); On-site; USD 80,000 - 115,000; Full time

Job summary

JMARK – IT Support and IT Services in Tulsa seeks a Network Engineer III to maintain, troubleshoot, and optimize complex enterprise networks for a key banking client.

You'll configure switches/routers, monitor performance, implement security controls, and collaborate with a team to deliver reliable, secure connectivity. Banking experience is a plus but not required; a strong problem-solving mindset is essential.

Qualifications

• 3–5 years of relevant network engineering experience.
• Advanced knowledge of enterprise networking: LAN/WAN, routing, switching, security.
• Experience configuring and troubleshooting Cisco equipment and firewall platforms.

Responsibilities

• Maintain, troubleshoot, secure, and improve complex network environments.
• Configure and manage switches, routers, firewalls, VPNs; ensure uptime and performance.
• Escalate and resolve issues; document configurations and solutions clearly.

Skills

Network engineering

Enterprise networking

Cisco equipment

Routing protocols

VLANs & IP

Firewalls & VPNs

Cisco ASA / Fortinet

Network monitoring

Security principles

Documentation

Tools

SSH

Wireshark

Job description

JMARK – IT Support and IT Services in Tulsa seeks a Network Engineer III to maintain, troubleshoot, and optimize complex enterprise networks for a key banking client.

You'll configure switches/routers, monitor performance, implement security controls, and collaborate with a team to deliver reliable, secure connectivity. Banking experience is a plus but not required; a strong problem-solving mindset is essential.