The edge of the cloud

By shifting the hardware and staffing costs of managing computational infrastructure to third parties, cloud computing has made it possible for small organizations and individuals to deploy world-scale services for only a fraction of the cost. At the same time, the deployment of 3G and 4G networks and the rapid adoption of feature-rich smartphones have brought mobile computing into the mainstream. The articles in this special explore the intersection of pervasive and cloud computing, focusing on data security and reliability issues. © 2002-2012 IEEE.