Shawn Lee

Highly accomplished Specialist with 30+ years of experience in mainframe TCP/IP, VTAM and enterprise-scale networking. Expert in implementing complex z/OS Communication Server features and optimizing data center infrastructures. Proven track record in resolving high-priority network bottlenecks through deep-dive packet analysis (Wireshark/Sniffer/Packet Trace) to ensure seamless, secure communication for Tier-1 financial institutions.

Senior z/OS Communication Server Specialist at Canada’s Largest Financial Institution | Toronto, ON | 2002 – Present

• z/OS Network Infrastructure: Led the support and implementation of z/OS Communication Server features including TCP/IP, VTAM, and Enterprise Extender (EE) for a global banking environment.

• Security Implementation: Enhanced system integrity by deploying advanced z/OS security features, including AT-TLS, IPSec, and Intrusion Detection Services (IDS).

• Performance Engineering: Act as the Tier-3 escalation point for complex connectivity issues between z/OS, end-users, and external vendors, utilizing Wireshark and Sniffer to reduce MTTR (Mean Time to Repair).

• Disaster Recovery: Redesign and implementation of GDPS network(TCPIP & APPN) ensuring 24/7 high availability for mission-critical banking applications.

• Legacy Integration: Managed the transition and coexistence of SNA/APPN and IP-based protocols within a modern data center framework.

• Data Center Network Support | 2015 – 2018 (Concurrent with z/OS support)

• Managed and configured Cisco enterprise-grade routers and switches to support core data center infrastructure.

• Resolved cross-platform application performance issues for internal business units and third-party vendors.

• Provided nationwide L2 support for IBM network products, including 3745/3746 Communication Controllers.

• Led network implementations for Fortune Global 500 clients, including Samsung, LG, and Hyundai.

• Developed and delivered technical training programs for field engineers.

• Provided hardware support for mainframe CPUs, storage (DASD), and massive transaction systems for major accounts such as Korean Air Lines & LG-EDS.

Bachelor of Electrical Engineering | Korea University, 1989