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Design Rationale is the combination of the structure that underpins the design of a product, and the reasoning behind it. This paper details the findings of ongoing research into the creation of a Remanufacturing Design Platform Model (RDPM), focusing on understanding the rationale behind Design for Remanufacture (DfR), and investigating alternative design strategies, points in the process at which decisions regarding end of life reuse are made, and criteria and other factors which influence such decisions. Key criteria to be considered in the creation of a design rationale for remanufacturing are suggested. The main challenges for designers of "remanufacturable" products are also considered. [ABSTRACT FROM AUTHOR]

Remanufacturing is driven by different factors (such as extended economic profits, reduced environmental loading, social inclusion and job creation) and opposed by various barriers (such as reverse logistics, customer perception, product disassembly and component inspection). This paper details the results of two research surveys that have elicited the views of academics from around the world who are involved in remanufacturing research. The studies used the Delphi Technique to calibrate the different views on this broad and "open-ended" topic. The paper explains the Delphi Technique, the development of an online Delphi survey software tool and the STEEP (Social, Technical, Economic, Environmental, and Political) structure used for the surveys. The paper describes the process of using the Delphi Technique with the panel of academics, and shows the main results from each survey along with proposals for the continuing research agenda. [ABSTRACT FROM AUTHOR]

The extensible access control markup language (XACML) is the standard access control policy specification language of the World Wide Web. XACML does not provide exclusive accesses to globally resources. We do so by enhancing the policy execution framework with locks. [ABSTRACT FROM AUTHOR]

Physical security has received increased attention after 9/11. However, access control to physical units has not been explored much. On the other hand, there is a rich literature on access control to information. These two areas appear converging as seen by recent products and studies. However, use of different notations and implementation details make this convergence harder. We need to try to take this convergence at a more abstract level first. Although introduced about 10 years ago, security patterns have recently become accepted by industry and two books on this topic have appeared recently. Security patterns for information access control have appeared but now we extend this concept to access for physical units. The unification of information and physical access control is just beginning but the strong requirements of infrastructure protection will make this convergence to happen rapidly. Examining existing systems, industry standards and government regulations, we describe, in the form of patterns, the core set of features a physical access control system should have. The paper illustrates the structure and use of these patterns. [ABSTRACT FROM AUTHOR]

The database server is a crucial bottleneck in traditional inference control architecture, as it enforces highly computation-intensive auditing for all users who query the protected database. As a result, most auditing methods, though rigorously studied, can never be implemented in practice for protecting largescale real-world database systems. To shift this paradigm, we propose a new inference control architecture that will entrust inference control to each users platform, provided that the platform is equipped with trusted computing technology. The trusted computing technology is designed to attest the state of a users platform to the database server, so as to assure the server that inference control could be enforced as expected. A generic protocol is proposed to formalize the interactions between the users platform and database server. Any existing inference control technique can work with our protocol, for which the security properties are formally proven. Since each user's platform enforces inference control for its own queries, our solution avoids the bottleneck. [ABSTRACT FROM AUTHOR]

Modern information systems require temporal and privilege-consuming usage of digital objects. To meet these requirements, we present a new access control model-Times-based Usage Control (TUCON). TUCON extends traditional and temporal access control models with times-based usage control by defining the maximum times that a privilege can be exercised. When the usage times of a privilege is consumed to zero or the time interval of the usage is expired, the privilege exercised on the object is automatically revoked by the system. Formal definitions of TUCON actions and rules are presented in this paper, and the implementation of TUCON is discussed. [ABSTRACT FROM AUTHOR]

With the growing advancement of pervasive computing technologies, we are moving towards an era where spatio-temporal information will be necessary for access control. The use of such information can be used for enhancing the security of an application, and it can also be exploited to launch attacks. For critical applications, a formal model for spatio-temporal-based access control is needed that increases the security of the application and ensures that the location information cannot be exploited to cause harm. In this paper, we propose a spatio-temporal access control model, based on the Role-Based Access Control (RBAC) model, that is suitable for pervasive computing applications. We show the association of each component of RBAC with spatio-temporal information. We formalize the model by enumerating the constraints. This model can be used for applications where spatial and temporal information of a subject and an object must be taken into account before granting or denying access. [ABSTRACT FROM AUTHOR]

Despite the widespread adoption of Role-based Access Control (RBAC) models, new access control models are required for new applications for which RBAC may not be especially well suited and for which implementations of RBAC do not enable properties of access control policies to be adequately defined and proven. To address these issues, we propose a form of access control model that is based upon the key notion of an event. The access control model that we propose is intended to permit the representation of access control requirements in a distributed and changing computing environment, the proving of properties of access control policies defined in terms of our model, and direct implementations for access control checking. [ABSTRACT FROM AUTHOR]

Security and privacy concerns as well as legal considerations force many companies to encrypt the sensitive data in databases. However, storing the data in an encrypted format entails non-negligible performance penalties while processing queries. In this paper, we address several design issues related to querying encrypted data in relational databases. Based on our experiments, we propose new and efficient techniques to reduce the cost of cryptographic operations while processing different types of queries. Our techniques enable us not only to overlap the cryptographic operations with the IO latencies but also to reduce the number of block cipher operations with the help of selective decryption capabilities. [ABSTRACT FROM AUTHOR]

In this paper, we present the design of gVault, a cryptographic network file system that utilizes the data storage provided by Gmail's web-based email service. Such a file system effectively provides users with an easily accessible free network drive on the Internet. gVault provides numerous benefits to the users, including: a) Secure remote access: Users can access their data securely from any machine connected to the Internet; b) Availability: The data is available 24/7; and c) Storage capacity: Gmail provides a large amount of storage space to each user. In this paper, we address the challenges in design and implementation of gVault. gVault is fundamentally designed keeping an average user in mind. We introduce a novel encrypted storage model and key management techniques that ensure data confidentiality and integrity. An initial prototype of gVault is implemented to evaluate the feasibility of such a system. Our experiments indicate that the additional cost of security is negligible in comparison to the cost of data transfer. [ABSTRACT FROM AUTHOR]

In this paper we present the design of a scalable and secure cryptographic service that can be adopted to support large-scale networked systems, which may require strong authentication from a large population of users. Since the users may not be able to adequately protect their cryptographic credentials, our service leverages some better protected servers to help fulfill such authentication needs. Compared with previous proposals, our service has the following features: (1) it incorporates a 3-factor authentication mechanism, which facilitates compromise detection; (2) it supports immediate revocation of a cryptographic functionality in question; (3) the damage due to the compromise of a server is contained; (4) it is scalable and highly available. [ABSTRACT FROM AUTHOR]

Service-oriented architectures (SOAs) are increasingly gaining popularity due to their considerable flexibility and scalability in open IT-environments. Along with their rising acceptance comes the need for well suited security components. In this respect, access control and privacy emerged to crucial factors. Targeting the demands of a SOA, many promising authorization models have been developed, most notably the attribute-based access control (ABAC) model. In this paper we take up concepts from the OASIS XACML and WS-XACML specifications and introduce a dynamic ABAC system that incorporates privacy preferences of the service requestor in the access control process. Separating the Policy Decision Point from the service provider's premises, our infrastructure enables the deployment of alternative PDPs the service requestor can choose from. We employ a PKI to reflect the sufficient trust relation between the service provider and a potential PDP. Our work is carried out within the European research project Access-eGov that aims at a European-wide e-Government service platform. [ABSTRACT FROM AUTHOR]

The growing number of distributed information systems such as the internet has created a need for security in data sharing. When several autonomous parties attempt to share data, there is not necessarily any guarantee that the participants will share data truthfully. In fact, there is often a large incentive to engage in behavior that can sabotage the effectiveness of such a system. We analyze these situations in light of game theory, a mathematical model which permits us to consider behavior and choices for any autonomous party. This paper uses this theory to create a behavior enforcement method that does not need a central management system. We use a simple punishment method that is inherently available in most scenarios. Our approach is applicable to a variety of assured information sharing applications where the members of a coalition have to work together to solve a problem. [ABSTRACT FROM AUTHOR]

Today's computer systems face sophisticated intrusions during which multiple vulnerabilities can be combined for reaching an attack goal. The overall security of a network system cannot simply be determined based on the number of vulnerabilities. To quantitatively assess the security of networked systems, one must first understand which and how vulnerabilities can be combined for an attack. Such an understanding becomes possible with recent advances in modeling the composition of vulnerabilities as attack graphs. Based on our experiences with attack graph analysis, we explore different concepts and issues on a metric to quantify potential attacks. To accomplish this, we present an attack resistance metric for assessing and comparing the security of different network configurations. This paper describes the metric at an abstract level as two composition operators with features for expressing additional constraints. We consider two concrete cases. The first case assumes the domain of attack resistance to be real number and the second case represents resistances as a set of initial security conditions. We show that the proposed metric satisfies desired properties and that it adheres to common sense. At the same time, it generalizes a previously proposed metric that is also based on attack graphs. It is our belief that the proposed metric will lead to novel quantitative approaches to vulnerability analysis, network hardening, and attack responses. [ABSTRACT FROM AUTHOR]

The event-condition-action (ECA) paradigm holds enormous potential in pervasive computing environments. However, the problem of reliable delivery of event data, generated by low capability sensor devices, to more capable processing points and vice versa, needs to be addressed for the success of the ECA paradigm in this environment. The problem becomes interesting because strong cryptographic techniques for achieving integrity impose unacceptable overhead in many pervasive computing environments. We address this problem by sending the data over the path from the sensor node to the processing point that provides the best opportunity of reliable delivery among competing paths. This allows using much weaker cryptographic techniques for achieving security. The problem is modeled as a problem of determining the most reliable path - similar to routing problems in networks. We propose a trust-based metric for measuring reliability of paths. The higher the trust value of a path the more reliable it is considered. We propose techniques for estimating the trust levels of paths and propose a new algorithm for identifying the desired path. [ABSTRACT FROM AUTHOR]

Location based services, one of the promising markets of mobile commerce, aims at delivering point of need personalized information. Often, these services to be delivered are based on the prior knowledge of the profiles of mobile customers and security and privacy policies dictated by them. These policies may specify revealing the sensitive information of mobile customers (e.g., age, salary) selectively to specific merchants in return of receiving certain benefits (e.g., coupons, special discounts, etc.). As a result, the security policies in such an environment are characterized by spatial and temporal attributes of the mobile customers (location and time), as well as their profile attributes. The focus of this paper is to efficiently enforce such policies. In this regard, we propose a unified structure that is capable of indexing mobile customer (mobile object) locations and their profiles, and the authorizations stating their security and privacy policies. [ABSTRACT FROM AUTHOR]

The widespread adoption of mobile communication devices combined with technical improvements of location technologies are fostering the development of a new wave of applications that manage physical positions of individuals to offer location-based services for business, social or informational purposes. As an effect of such innovative services, however, privacy concerns are increasing, calling for more sophisticated solutions for providing users with different and manageable levels of privacy. In this work, we propose a way to express users privacy preferences on location information in a straightforward and intuitive way. Then, based on such location privacy preferences, we discuss a new solution, based on obfuscation techniques, which permits us to achieve, and quantitatively estimate through a metric, different degrees of location privacy. [ABSTRACT FROM AUTHOR]

We present a general method, based on the usage of typical DBMS primitives, for maintaining authenticated relational tables. The authentication process is managed by an application external to the DBMS, that stores just one hash information of the authentication structure. The method exploits techniques to represent hierarchical data structures into relational tables and queries that allow an efficient selection of the elements needed for authentication. [ABSTRACT FROM AUTHOR]

In this paper, we take a closer look at the security of outsourced databases (aka Database-as-the-Service or DAS), a topic of emerging importance. DAS allows users to store sensitive data on a remote, untrusted server and retrieve desired parts of it on request. At first we focus on basic, exact-match query functionality, and then extend our treatment to prefix-matching and, to a more limited extent, range queries as well. We propose several searchable encryption schemes that are not only practical enough for use in DAS in terms of query-processing efficiency but also provably-provide privacy and authenticity of data under new definitions of security that we introduce. The schemes are easy to implement and are based on standard cryptographic primitives such as block ciphers, symmetric encryption schemes, and message authentication codes. As we are some of the first to apply the provable-security framework of modern cryptography to this context, we believe our work will help to properly analyze future schemes and facilitate further research on the subject in general. [ABSTRACT FROM AUTHOR]

Controlled Query Evaluation (CQE) is an approach to enforcing confidentiality in information systems at runtime. At each query, a censor checks whether the answer to that query would enable the user to infer any information he is not allowed to know according to some specified confidentiality policy. If this is the case, the answer is distorted, either by refusing to answer or by returning a modified answer. In this paper, we consider incomplete logic databases and investigate the semantic ways of protecting a piece of information. We give a formal definition of such confidentiality policies, and show how to enforce them by reusing the existing methods for CQE. [ABSTRACT FROM AUTHOR]

We demonstrate how access control models and policies can be represented by using term rewriting systems, and how rewriting may be used for evaluating access requests and for proving properties of an access control policy. We focus on two kinds of access control models: discretionary models, based on access control lists (ACLs), and role-based access control (RBAC) models. For RBAC models, we show that we can specify several variants, including models with role hierarchies, and constraints and support for security administrator review querying. [ABSTRACT FROM AUTHOR]