Automatic Resource Allocation for High Availability Cloud Services

AbstractThis paper proposes an approach to support cloud brokers finding optimal configurations in the deployment of dependability and security sensitive cloud applications. The approach is based on model-driven principles and uses both UML and Bayesian Networks to capture, analyse and optimise cloud deployment configurations. While the paper is most focused on the initial allocation phase, the approach is extensible to the operational phases of the life-cycle. In such a way, a continuous improvement of cloud applications may be realised by monitoring, enforcing and re-negotiating cloud resources following detected anomalies and failures

AMADEOS SysML Profile for SoS Conceptual Modeling

International audienc

Supporting ISO 26262 with SysML, Benefits and Limits

International audienceThis article deals with the issue of deploying efficiently the ISO 26262: the new standard in automotive systems development. The directives enclosed in this norm demands the establishment of a product lifecycle fully integrating the safety assessment activities. To tackle this subject, this paper explores the way of setting up Model-Based Design methodology to express and organize the concepts manipulated during the ISO 26262 process. This attempt is founded on the use of SysML and on the creation of a profile dedicated to ISO 26262 development context. We provide an introduction to Model-Based Design paradigm and its appli-cation in a safety relevant context. An overview of ISO 26262 is given, followed by the description of an on-going project on the subject. Modeling propositions are formulated and the use of diverse SysML diagrams are mapped on the automotive safety lifecycle process

A Petri Net Tool for Software Performance Estimation Based on Upper Throughput Bounds

Functional and non-functional properties analysis (i.e., dependability, security, or performance) ensures that requirements are fulfilled during the design phase of software systems. However, the Unified Modelling Language (UML), standard de facto in industry for software systems modelling, is unsuitable for any kind of analysis but can be tailored for specific analysis purposes through profiling. For instance, the MARTE profile enables to annotate performance data within UML models that can be later transformed to formal models (e.g., Petri nets or Timed Automatas) for performance evaluation. A performance (or throughput) estimation in such models normally relies on a whole exploration of the state space, which becomes unfeasible for large systems. To overcome this issue upper throughput bounds are computed, which provide an approximation to the real system throughput with a good complexity-accuracy trade-off. This paper introduces a tool, named PeabraiN, that estimates the performance of software systems via their UML models. To do so, UML models are transformed to Petri nets where performance is estimated based on upper throughput bounds computation. PeabraiN also allows to compute other features on Petri nets, such as the computation of upper and lower marking place bounds, and to simulate using an approximate (continuous) method. We show the applicability of PeabraiN by evaluating the performance of a building closed circuit TV system