  Digital media has been increasing very rapidly, resulting in cloud
computing's popularity gain. Cloud computing provides ease of management of
large amount of data and resources. With a lot of devices communicating over
the Internet and with the rapidly increasing user demands, solitary clouds have
to communicate to other clouds to fulfill the demands and discover services
elsewhere. This scenario is called intercloud computing or cloud federation.
Intercloud computing still lacks standard architecture. Prior works discuss
some of the architectural blueprints, but none of them highlight the key issues
involved and their impact, so that a valid and reliable architecture could be
envisioned. In this paper, we discuss the importance of intercloud computing
and present in detail its architectural components. Intercloud computing also
involves some issues. We discuss key issues as well and present impact of
storage heterogeneity. We have evaluated some of the most noteworthy cloud
storage services, namely Dropbox, Amazon CloudDrive, GoogleDrive, Microsoft
OneDrive (formerly SkyDrive), Box, and SugarSync in terms of Quality of
Experience (QoE), Quality of Service (QoS), and storage space efficiency.
Discussion on the results shows the acceptability level of these storage
services and the shortcomings in their design.
