3781878
Applying SDL to Formal Analysis of Security Systems
Nowadays, it is widely accepted that critical systems have to be formally analyzed to achieve well-known benefits of formal methods. To study the security of communication systems, we have developed a methodology for the application of the formal analysis techniques commonly used in communication protocols to the analysis of cryptographic ones. In particular, we have extended the design and analysis phases with security properties. Our proposal uses a specification notation based on MSC, which can be automatically translated into a generic SDL specification. This SDL system can then be used for the analysis of the desired security properties, by using an observer process schema. Apart from our main goal of providing a notation for describing the formal specification of security systems, our proposal also brings additional benefits, such as the study of the possible attacks to the system, and the possibility of reusing the specifications produced to describe and analyze more complex systems.
11647123
Non-repudiation protocols for multiple entities
Non-repudiation is a security service that provides cryptographic evidence to support the settlement of disputes. In this paper, we introduce the state-of-the-art of non-repudiation protocols for multiple entities. We extend an existing multi-party non-repudiation (MPNR) protocol to allow an originator to send different messages to many recipients in a single transaction. We further propose an optimistic multi-party non-repudiation protocol for exchange of different messages. The performance of our protocols with enhanced functionalities is still promising in comparison with existing MPNR protocols.
18811883
Authentication and authorization infrastructures (AAIs): a comparative survey
In this article, we argue that traditional approaches for authorization and access control in computer systems (i.e., discretionary, mandatory, and role-based access controls) are not appropriate to address the requirements of networked or distributed systems, and that proper authorization and access control requires infrastructural support in one way or another. This support can be provided, for example, by an authentication and authorization infrastructure (AAI). Against this background, we overview, analyze, discuss, and put into perspective some technologies that can be used to build and operate AAIs. More specifically, we address Microsoft .NET Passport and some related activities (e.g. the Liberty Alliance Project), Kerberos-based solutions, and AAIs that are based on digital certificates and public key infrastructures (PKIs). We conclude with the observation that there is no single best approach for providing an AAI, that every approach has specific advantages and disadvantages, and that a comprehensive AAI must combine various technologies and approaches.
3856838
Trust, Privacy and Security in E-Business: Requirements and Solutions
An important aspect of e-business is the area of e-commerce. One of the most severe restraining factors for the proliferation of e-commerce, is the lack of trust between customers and sellers, consumer privacy concerns and the lack of security measures required to assure both businesses and customers that their business relationship and transactions will be carried out in privacy, correctly, and timely. This paper considers trust privacy and security issues in e-commerce applications and discusses methods and technologies that can be used to fulfil the pertinent requirements.
3098775
A First Approach to Provide Anonymity in Attribute Certificates
This paper focus on two security services for internet ap- plications: authorization and anonymity. Traditional authorization solu- tions are not very helpful for many of the Internet applications; however, attribute certificates proposed by ITU-T seems to be well suited and provide adequate solution. On the other hand, special attention is paid to the fact that many of the operations and transactions that are part of Internet applications can be easily recorded and collected. Consequently, anonymity has become a desirable feature to be added in many cases. In this work we propose a solution to enhance the X.509 attribute certifi- cate in such a way that it becomes a conditionally anonymous attribute certificate. Moreover, we present a protocol to obtain such certificates in a way that respects users' anonymity by using a fair blind signature scheme. We also show how to use such certificates and describe a few cases where problems could arise, identifying some open problems.
3774705
On Secure Profiling
Ubiquitous environments have several drawbacks to be solved. Most of them are focused on security, and relevant ones are authorization and authentication. Amongst the essential elements to adequately provide solutions, we can find profiles. A profile can be defined as a repository to store structured data from users, networks, devices, applications, etc. As profiles are needed in ubiquitous environments, and these need of secure management as well, in this paper, we provide some initial guidance on the security storage of profiles and on security levels needed for each type of profile. Additionally, we review different alternatives to bear profiles, concluding that smart cards are the most suitable devices
467068
Run-Time Support for Adaptive Heavyweight Services
By definition, a heavyweight network service requires a significant amount of computation to complete its task. Providing a heavyweight service is challenging for a number of reasons. First, since the service can typically not be provided in a timely fashion using a single server at the remote site, multiple hosts at both the server and client sites must be employed. Second, the available compute and network resources change with respect to time. Thus, an effective service must be adaptive in the sense that it is able to transparently aggregate the available resources and react to the changing availability of these resources. In this paper we present a framework that allows us to build these kinds of adaptive heavyweight services. Experimental results with a distributed visualization service suggest that the cost imposed by the new capability is reasonable.
1480760
Evaluation of a resource selection mechanism for complex network services
Providing complex (resource-intensive) network services is challenging because the resources they need and the resources that are available can vary significantly from request to request. To address this issue, we have proposed a flexible mechanism, called active frames, that provides a basis for selecting a set of available distributed computing resources, and then mapping tasks onto those resources. As a proof of concept, we have used active frames to build a remote visualization service, called Dv, that allows users to visualize the contents of scientific datasets stored at remote locations. We evaluate the performance of active frames, in the context of Dv. In particular, we address the following two questions: (1) what performance penalty do we pay for the flexibility of the active frames mechanism? (2) can the throughput of a service based on active frames be predicted with reasonable accuracy from micro-benchmarks? The results of the evaluation suggest that the overhead imposed by active frames is reasonable (roughly 5%), and that simple models based on micro-benchmarks can conservatively predict measured throughput with reasonable accuracy (at most 20%).
1101949
Preliminary Report on the Design of a Framework for Distributed Visualization
The paper is a preliminary report on the de- sign of a framework, called Dv, for building interactive distributed visualizations on computational grids. The framework is based on a form of mobile object, called an active frame, that consists of application data and a pro- gram that manipulates the data. The system provides a flexible framework for building distributed applications that are performance-portable in the presence of hetero- geneous resources and that adapt to dynamic changes in the status of system resources such as processor cycles and network bandwidth.