Mainframe Network Engineer

This is a contract position for a Mainframe Network Engineer based in Phoenix, Arizona, with an expected duration of 12+ months. The role focuses on designing, configuring, implementing, and supporting network connectivity for IBM mainframe environments, ensuring reliable, secure, and high-performing communication between mainframe systems, distributed platforms, external partners, and enterprise applications.

Responsibilities

• Install, configure, and maintain z/OS Communications Server components
• Support and manage TCP/IP configuration on z/OS systems
• Maintain and troubleshoot VTAM definitions and network resources
• Configure and support Enterprise Extender (EE) and SNA connectivity where applicable
• Maintain TN3270 access and session-related connectivity for end users and applications
• Ensure stable communication between mainframe systems and distributed servers, external vendors/partners, internal enterprise applications, and middleware platforms
• Diagnose and resolve connectivity issues involving IP routing, port communication, session failures, DNS resolution, and firewall-related blocks
• Support file transfer protocols such as FTP, SFTP, and other secure data exchange solutions
• Work closely with network security teams to enforce secure communication protocols
• Ensure compliance with enterprise security controls and audit requirements
• Support SSL/TLS certificate implementation and secure transmission standards
• Assist with firewall rule validation, port usage reviews, and vulnerability remediation
• Support network design and recovery procedures for Disaster Recovery (DR) environments
• Validate communication paths for failover systems and backup data centers
• Participate in DR tests and business continuity exercises

Qualifications

• Demonstrated experience with z/OS Communications Server administration and configuration
• Strong knowledge of TCP/IP, VTAM, SNA, and related mainframe networking protocols
• Experience with Enterprise Extender (EE) and TN3270 connectivity
• Proficiency in troubleshooting mainframe network connectivity issues
• Experience with file transfer protocols including FTP and SFTP
• Understanding of network security principles, SSL/TLS, and secure transmission standards
• Familiarity with firewall configuration and network security compliance
• Experience supporting Disaster Recovery and business continuity initiatives
• Ability to work effectively with cross-functional teams including security and infrastructure teams