But opinions within government are shifting, and it is telling that the panelists cited procedural factors like the minutia of the procurement process as the biggest impediments to federal adoption of cloud technologies, rather than more familiar concerns such as security.

"We still have a traditional procurement model in the federal government," Adams says. "When you get to the cloud you have these standard commercial contracts that no agency will accept."

Adams says that the service-level agreements that Microsoft and other cloud providers routinely include in their contracts with commercial customers don't pass muster with the agencies, which also operate under compliance obligations relating to a number of security standards unique to the federal government. Taken together, these factors mean that cloud vendors often have to rewrite their contracts, which can be hundreds of pages, from scratch in a negotiated process with their government customers.

"That's probably the biggest challenge," Adams says.

Agencies also face familiar challenges that are common to the private sector when mulling cloud deployments, particularly at the infrastructure level. Fears about vendor lock-in, for instance, suggest that agencies might need to rethink their IT architecture to ensure that they retain the flexibility to shift from one provider to another, as the need arises.