3,341 research outputs found
PaPaS: A Portable, Lightweight, and Generic Framework for Parallel Parameter Studies
The current landscape of scientific research is widely based on modeling and
simulation, typically with complexity in the simulation's flow of execution and
parameterization properties. Execution flows are not necessarily
straightforward since they may need multiple processing tasks and iterations.
Furthermore, parameter and performance studies are common approaches used to
characterize a simulation, often requiring traversal of a large parameter
space. High-performance computers offer practical resources at the expense of
users handling the setup, submission, and management of jobs. This work
presents the design of PaPaS, a portable, lightweight, and generic workflow
framework for conducting parallel parameter and performance studies. Workflows
are defined using parameter files based on keyword-value pairs syntax, thus
removing from the user the overhead of creating complex scripts to manage the
workflow. A parameter set consists of any combination of environment variables,
files, partial file contents, and command line arguments. PaPaS is being
developed in Python 3 with support for distributed parallelization using SSH,
batch systems, and C++ MPI. The PaPaS framework will run as user processes, and
can be used in single/multi-node and multi-tenant computing systems. An example
simulation using the BehaviorSpace tool from NetLogo and a matrix multiply
using OpenMP are presented as parameter and performance studies, respectively.
The results demonstrate that the PaPaS framework offers a simple method for
defining and managing parameter studies, while increasing resource utilization.Comment: 8 pages, 6 figures, PEARC '18: Practice and Experience in Advanced
Research Computing, July 22--26, 2018, Pittsburgh, PA, US
The case for cloud service trustmarks and assurance-as-a-service
Cloud computing represents a significant economic opportunity for Europe. However, this growth is threatened by adoption barriers largely related to trust. This position paper examines trust and confidence issues in cloud computing and advances a case for addressing them through the implementation of a novel trustmark scheme for cloud service providers. The proposed trustmark would be both active and dynamic featuring multi-modal information about the performance of the underlying cloud service. The trustmarks would be informed by live performance data from the cloud service provider, or ideally an independent third-party accountability and assurance service that would communicate up-to-date information relating to service performance and dependability. By combining assurance measures with a remediation scheme, cloud service providers could both signal dependability to customers and the wider marketplace and provide customers, auditors and regulators with a mechanism for determining accountability in the event of failure or non-compliance. As a result, the trustmarks would convey to consumers of cloud services and other stakeholders that strong assurance and accountability measures are in place for the service in question and thereby address trust and confidence issues in cloud computing
Quire: Lightweight Provenance for Smart Phone Operating Systems
Smartphone apps often run with full privileges to access the network and
sensitive local resources, making it difficult for remote systems to have any
trust in the provenance of network connections they receive. Even within the
phone, different apps with different privileges can communicate with one
another, allowing one app to trick another into improperly exercising its
privileges (a Confused Deputy attack). In Quire, we engineered two new security
mechanisms into Android to address these issues. First, we track the call chain
of IPCs, allowing an app the choice of operating with the diminished privileges
of its callers or to act explicitly on its own behalf. Second, a lightweight
signature scheme allows any app to create a signed statement that can be
verified anywhere inside the phone. Both of these mechanisms are reflected in
network RPCs, allowing remote systems visibility into the state of the phone
when an RPC is made. We demonstrate the usefulness of Quire with two example
applications. We built an advertising service, running distinctly from the app
which wants to display ads, which can validate clicks passed to it from its
host. We also built a payment service, allowing an app to issue a request which
the payment service validates with the user. An app cannot not forge a payment
request by directly connecting to the remote server, nor can the local payment
service tamper with the request
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