Mobile payments still remain essentially an emerging technology, seeking to fill the gap between the envisioned potential and widespread usage. In this paper, we present an integrated mobile service solution based on the near field communication (NFC) protocol that was developed under a research project called MobiPag. The most distinctive characteristic of Mobipag is its open architectural model that allows multiple partners to become part of the payment value-chain and create solutions that complement payments in many unexpected ways. We describe the Mobipag architecture and how it has been used to support a mobile payment trial. We identify a set of design lessons resulting from usage experiences associated with real-world payment situations with NFC-enabled mobile phones. Based on results from this trial, we identify a number of challenges and guidelines that may help to shape future versions of NFC-based payment systems. In particular, we highlight key challenges for the initial phases of payment deployments, where it is essential to focus on scenarios that can be identified as more feasible for early adoption. We also have identified a fundamental trade-off between the flexibility supported by the Mobipag solution and the respective implications for the payment process, particularly on the users’ mental model.

Traditionally, a country's electoral system requires the voter to vote at a specific day and place, which conflicts with the mobility usually seen in modern live styles. Thus, the widespread of Internet (mobile) broadband access can be seen as an opportunity to deal with this mobility problem, i.e. the adoption of an Internet voting system can make the live of voter's much more convenient; however, a widespread Internet voting systems adoption relies on the ability to develop trustworthy systems, i.e. systems that are verifiable and preserve the voter's privacy. Building such a system is still an open research problem. Our contribution is a new Internet voting system: EVIV, a highly sound End-to-end Verifiable Internet Voting system, which offers full voter's mobility and preserves the voter's privacy from the vote casting PC even if the voter votes from a public PC, such as a PC at a cybercafé or at a public library. Additionally, EVIV has private vote verification mechanisms, in which the voter just has to perform a simple match of two small strings (4–5 alphanumeric characters), that detect and protect against vote manipulations both at the insecure vote client platform and at the election server side.

Code voting is a technique used to address the secure platform problem of remote voting. A code voting system consists in secretly sending, e.g. by mail, code sheets to voters that map their choices to entry codes in their ballot. While voting, the voter uses the code sheet to know what code to enter in order to vote for a particular candidate. In effect, the voter does the vote encryption and, since no malicious software on the PC has access to the code sheet it is not able to change the voter’s intention. However, without compromising the voter’s privacy, the vote codes are not enough to prove that the vote is recorded and counted as cast by the election server. We present a voter verifiable code voting solution which, without revealing the voter’s vote, allows the voter to verify, at the end of the election, that her vote was cast and counted as intended by just performing the match of a few small strings. Moreover, w.r.t. a general code voting system, our solution comes with only a minor change in the voting interaction.

The arising of grid platforms introduced inexpensive and highly available computing, storage and networking resources. Therefore, in a worldwide trend, institutions aggregate on virtual organizations, registering their resources to the grid and in return accessing a virtually limitless warehouse. This overabundance allowed the emergence of innovative application and business models, delivering the solution to several large-scale problems, as is the case of data processing, storage and sharing in CERN's Large Hadron Collider Project. In order to allow system administrators to assure resources are employed in a coordinated and secure way, policy mechanisms need to cope with such new models and the increased complexity in resource usage management. However, current grid platforms only provide simple primitives in their authorization modules. By restricting access control mechanisms to ACLs and role-based models, they disregard powerful usage semantics, such as those which are history-based (e.g. the Chinese-wall security policy). This absence obliges the development of ad hoc security managers for each deployed resource, introducing vulnerabilities in the security architecture. The use of advanced policies, and more specifically history-based policies, provides a natural method for expressing and enforcing several grid usage patterns, such as fair resource consumption. Additionally, some policy concepts not usually found in policy engines, such as periodic reevaluation, assure an effective policy enforcement. We present the Heimdhal system, a history-enabled policy engine which allows the definition, enforcement and accounting of history-based policies in grid platforms, and more specifically in Globus Toolkit 4.0. A practical evaluation using selected usage patterns corroborates the effectiveness of this kind of policies in grid computing environments, denoting encouraging performance results.