300 research outputs found
Encryption under threat: as states across the globe weaken cyber-security - Germany should oppose the trend
An inadvertent worldwide alliance against encryption is emerging, as Western democracies join authoritarian regimes in weakening communication encryption and exploiting spyware. This accelerating global trend undermines efforts to enhance cyber-security. Germany should oppose such developments and intensify its efforts to champion encryption. This will also mean finding alternative instruments to keep terrorism suspects under surveillance without degrading the software security of the entire population. (author's abstract
Scalable desktop grid system
Desktop grids are easy to install on large number of personal computers, which is a prerequisite for the spread of grid technology. Current desktop grids connect all PCs into a flat hierarchy, that is, all computers to a central server. SZTAKI Desktop Grid starts from a standalone desktop grid, as a building block. It is extended to include clusters displaying as single powerful PCs, while using their local resource management system. Such building blocks support overtaking additional tasks from other desktop grids, enabling the set-up of a hierarchy. Desktop grids with different owners thus can share resources, although only in a hierarchical structure. This brings desktop grids closer to other grid technologies where sharing resources by several users is the most important feature
Application Monitoring in the Grid with GRM and PROVE
Abstract. GRM and PROVE were originally designed and implemented as part of the P-GRADE graphical parallel program development environment running on clusters. In the framework of the biggest European Grid project, the DataGrid project we investigated the possibility of transforming GRM and PROVE to a Grid monitoring infrastructure. This paper presents the results of this work showing how to separate GRM and PROVE from the P-GRADE system and to turn them into standalone Grid monitoring tools
Virtual appliance size optimization with active fault injection
Virtual appliances store the required information to instantiate a functional Virtual Machine (VM) on Infrastructure as a Service (IaaS) cloud systems. Large appliance size obstructs IaaS systems to deliver dynamic and scalable infrastructures according to their promise. To overcome this issue, this paper offers a novel technique for virtual appliance developers to publish appliances for the dynamic environments of IaaS systems. Our solution achieves faster virtual machine instantiation by reducing the appliance size while maintaining its key functionality. The new virtual appliance optimization algorithm identifies the removable parts of the appliance. Then, it applies active fault injection to remove the identified parts. Afterward, our solution assesses the functionality of the reduced virtual appliance by applying the-appliance developer provided-validation algorithms. We also introduce a technique to parallelize the fault injection and validation phases of the algorithm. Finally, the prototype implementation of the algorithm is discussed to demonstrate the efficiency of the proposed algorithm through the optimization of two well-known virtual appliances. Results show that the algorithm significantly decreased virtual machine instantiation time and increased dynamism in IaaS systems. © 2012 IEEE
GridCertLib: a Single Sign-on Solution for Grid Web Applications and Portals
This paper describes the design and implementation of GridCertLib, a Java
library leveraging a Shibboleth-based authentication infrastructure and the
SLCS online certificate signing service, to provide short-lived X.509
certificates and Grid proxies. The main use case envisioned for GridCertLib, is
to provide seamless and secure access to Grid/X.509 certificates and proxies in
web applications and portals: when a user logs in to the portal using
Shibboleth authentication, GridCertLib can automatically obtain a Grid/X.509
certificate from the SLCS service and generate a VOMS proxy from it. We give an
overview of the architecture of GridCertLib and briefly describe its
programming model. Its application to some deployment scenarios is outlined, as
well as a report on practical experience integrating GridCertLib into portals
for Bioinformatics and Computational Chemistry applications, based on the
popular P-GRADE and Django softwares.Comment: 18 pages, 1 figure; final manuscript accepted for publication by the
"Journal of Grid Computing
Workflow level interoperation of grid data resources
The lack of widely accepted standards and the use of different middleware solutions divide today’s Grid resources into non-interoperable production Grid islands. On the other hand, more and more experiments require such a large number of resources that the interoperation of existing production Grids becomes inevitable. This paper, based on the current results of grid interoperation studies, defines generic requirements towards the workflow level interoperation of grid solutions. It concentrates on intra-workflow interoperation of grid data resources, as one of the key areas of generic interoperation, and describes through an example how existing tools can be extended to achieve the required level of interoperation
A general and scalable solution for heterogeneous workflow invocation and nesting
Several widely utilized, grid workflow management systems emerged in the last decade. These systems were developed by different scientific communities for various purposes. Enhancing these systems with the capability of invoking and nesting the workflows of other systems within their native workflows makes these communities to be able to carry out cross-organizational experiments and share non-native workflows. The novel solution described in this paper allows the integration of different workflow engines and makes them accessible for workflow systems in order to achieve this goal. The solution is based on an application repository and submitter, which exposes different workflow engines and executes them using the computational resources of the grid. In contrast with other approaches, our solution is scalable in terms of both number of workflows and amount of data, easily extendable in the sense that the integration of a new workflow engine does not require code re-engineering, and general, since it can be adopted by numerous workflow systems
Creating scalable traffic simulation on clusters
We describe the implementation of a transport simulation in a parallel environment. The implementation is based on a graphical parallel programming environment called P-GRADE. The transport simulator, called MadCity, simulates a specific road network of a city and shows cars moving on the roads. To achieve scalability of the traffic simulation, the use of templates is necessary. This helps to control the number of participating processes required for the simulation without making modifications to the simulator's source code. Performance results are collected from four, eight and sixteen nodes of the Parsifal cluster and compared with the sequential execution results of the simulator. The implementation of the transport simulator is extended further to support the simulation of multiple cities within the same cluster and on the Grid
- …