Cloud computing improves utilization and flexibility in allocating computing resources while reducing the infrastructural costs. However, in many cases cloud technology is still proprietary and tainted by security issues rooted in the multi-user and hybrid cloud environment. A lack of secure connectivity in a hybrid cloud environment hinders the adaptation of clouds by scientific communities that require scaling-out of the local infrastructure using publicly available resources for large-scale experiments. In this article, we present a case study of the DII-HEP secure cloud infrastructure and propose an approach to securely scale-out a private cloud deployment to public clouds in order to support hybrid cloud scenarios. A challenge in such scenarios is that cloud vendors may offer varying and possibly incompatible ways to isolate and interconnect virtual machines located in different cloud networks. Our approach is tenant driven in the sense that the tenant provides its connectivity mechanism. We provide a qualitative and quantitative analysis of a number of alternatives to solve this problem. We have chosen one of the standardized alternatives, Host Identity Protocol, for further experimentation in a production system because it supports legacy applications in a topologically-independent and secure way.

We report a novel deployment of so-called UBI-hotspots in a city center to establish an ecosystem infrastructure for conducting diverse urban computing research and business in authentic urban setting. We focus on the value network of the hotspots where the commercial use of the hotspots generates revenue for covering their operational expenses. The value network has been validated by a 12-month long operation, during which the hotspots and their services have been available to the general public on 24/7 basis.

In this paper we present a web-based framework for spatiotemporal screen real estate management of interactive public displays. The framework facilitates dynamic partitioning of the screen real estate into virtual screens assigned for multiple concurrent web applications. The framework is utilized in the implementation of so-called UBI-hotspot, which provides various information services via different interaction modalities including mobile. The framework facilitates seamless integration of third party web applications residing anywhere in the public Internet into the UBI-hotspot, thus catering for a scalable and open architecture. We report the deployment of a network of indoor and outdoor UBI-hotspots at downtown Oulu, Finland. The quantitative data on the usage of the UBI-hotspots implicitly speaks in favor of the practical applicability of the framework.

ARC and gLite are two of the leading production-ready Grid middleware solutions being used by thousands of researchers every day. Even though the middlewares leverage the same technologies, there are substantial architectural and implementation divergences. Today, users face difficulties trying to cross the boundaries of the two systems. The gLite clients have so far not been capable of accessing ARC resources and vice versa. This paper is a follow up on an earlier proposal on how to enable interoperability between these two middlewares. Further, the paper presents a thorough walkthrough of the protocols and steps involved in the submission of a job in grids built up of the two different middlewares.