Contributing Authors

Don Happe has more than 17 years of industry experience in internetworking, server operating systems, messaging, and directory services consulting. At Callisma Don founded the Enterprise Operating Systems practice and is the National Practice Director. The Enterprise Operating Systems practice focuses on delivering strategic and project-based solutions to Callisma's clients in the areas of server consolidation and virtualization; directory services; identity management; provisioning; and messaging-related projects. Don has extensive experience in the planning, design, and implementation of enterprise technologies. He is also proficient at program/project management, strategic planning, architecture and design, and pilot/full-scale deployments. Before joining Callisma, Don worked for Computer Sciences Corporation, where he led various large-scale data center, network operating systems, and internetworking projects.

Gary J. Humphrey has more than 25 years of industry experience in networking, security, and data communications. Before joining Callisma, he held positions as senior director, architect, vice president, and president with Fortune 50/100/250 companies, along with foreign military security communications design companies. Previous design and implementations of GSX and ESX include the consolidation of more than 2,500 servers into VMware environments. He holds degrees in Petroleum Land Management and Business, with professional certifications of CISSP, MCSE2K3, CISSM, CISA, CCNA, CCDA, and CCA. Currently, he is involved in SOX security audits and the design of role-based access control models for Fortune 100 companies.