"Now we're finding we have utility programs that are driving our life cycle," says Kahn.

The availability of operating system patches and updates is another major factor. "We went from having the applications being our biggest concern to making sure our operating system was up to date and patched properly," Kahn says. Operating system upgrades must be planned for and completed before Microsoft drops security update support for the operating systems currently in use.

"For us, it's software rather than the hardware that is driving it," Kahn says.

SIDEBAR

Counterpoint: The case for shorter life cycles