And in the hotel business, e-mail can't go down. So with a lean IT staff, the key was to build bulletproof e-mail without the amount of work it usually takes to build a Microsoft Exchange network that's 100 percent reliable.

How did they do it? Beggs shared her 6 tips for building bulletproof Exchange e-mail in the cloud:

1. Define the business risk and what you're able to do to minimize it.

Without the budget or willingness to build expensive high availability/business continuity systems, Sonesta's only real choice was to have someone else handle the insurance systems.

"We realized how mission critical e-mail is and, while I had confidence in our backup routines, I still wanted an additional layer of protection," Beggs says. "If we ever had a catastrophe or had a server go down, I wanted to have some extra backup available so we wouldn't have the additional risk."