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.
7567479
Stardust: tracking activity in a distributed storage system
Performance monitoring in most distributed systems provides minimal guidance for tuning, problem diagnosis, and decision making. Stardust is a monitoring infrastructure that replaces traditional performance counters with end-to-end traces of requests and allows for efficient querying of performance metrics. Such traces better inform key administrative performance challenges by enabling, for example, extraction of per-workload, per-resource demand information and per-workload latency graphs. This paper reports on our experience building and using end-to-end tracing as an on-line monitoring tool in a distributed storage system. Using diverse system workloads and scenarios, we show that such fine-grained tracing can be made efficient (less than 6% overhead) and is useful for on- and off-line analysis of system behavior. These experiences make a case for having other systems incorporate such an instrumentation framework.
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.
3830604
A Synchronous Multi-Party Contract Signing Protocol Improving Lower Bound of Steps
Contract signing is a fundamental service in doing business. The Internet has facilitated the electronic commerce, and it is necessary to find appropriate mechanisms for contract signing in the digital world. A number of two-party contract signing protocols have been proposed with various features. Nevertheless, in some applications, a contract may need to be signed by multiple parties. Less research has been done on multi-party contract signing. In this paper, we propose a new synchronous multi-party contract signing protocol that, with n parties, it reaches a lower bound of 3(n − 1) steps in the all-honest case and 4n − 2 steps in the worst case (i.e., all parties contact the trusted third party). This is so far the most efficient synchronous multi-party contract signing protocol in terms of the number of messages required. We further consider the additional features like timeliness and abuse-freeness in the improved version.
3850726
XML-Based Distributed Access Control System
The use of attribute certificates andthe concept of mobile policies have been proposed to overcome some of the limitations of the role based access control (RBAC) paradigm and to implement security requirements such as the "originator controlled" (ORCON) policy. Mobile policies are attached to the data that they control and enforced by their execution in trusted servers. In this paper we extend this idea to allow the execution of the policies in untrusted systems. Our extension allows policies to be bound to the data but not attached to. Through this modification security administrators are able to change policies dynamically and transparently. Additionally, we introduce X-ACS, an XML-based language designedto express policies in a simple and unambiguous way overcoming the limitations of other approaches. Important features of X-ACS are that it can be used by processors with limited capabilities such as smart cards while allowing the automated validation of policies.