One is to use commercial services such as those offered by Amazon and Google. Examples include the migrations of Treasury.gov and Recovery.gov to Amazon's cloud service.

The second is to share services within the government, where one agency acts as a service provider for others. Examples of this are DISA's RACE system and NASA's Nebula.

The third option is to build a private cloud for an organization's exclusive use.

Francesca and Raines point out that government CIOs have such diverse systems that they can legitimately use any of those approaches, depending on the needs of the applications and data slated for migration to the cloud.

The General Services Administration and the National Institute of Standards and Technology (NIST) are helping federal agencies with their cloud computing moves, according to Francesca and Raines.