What’s New in V2 of the Architecture Analysis & Design Language Standard?

<p>This report provides an overview of changes and improvements to the Architecture Analysis & Design Language (AADL) standard for describing both the software architecture and the execution platform architectures of performance-critical, embedded, real-time systems. The standard was initially defined in the document SAE AS-5506 and published in November 2004 by SAE International (formerly the Society of Automotive Engineers). SAE International published the revised language, known as AADL V2, in January 2009. Feedback from users of the standard guided the plan for improvements. Their experience and suggestions resulted in the addition of component categories to better represent protocols as logical entities (virtual bus), scheduler hierarchies and logical time partitions (virtual processor), and a generic component (abstract). The revisions also led to the abilities to (1) explicitly parameterize component declarations to better express architecture patterns, (2) specify multiple instances of the same component in one declaration (component array) and corresponding connection patterns, (3) set visibility rules for packages and property sets that access other packages and property sets, (4) specify system-level mode transitions more precisely, and (5) use additional property capabilities including property value records.</p

Resource Allocation in Dynamic Environments

<p>This technical report examines two challenges related to resource allocation that can negatively affect system operation in a dynamic environment, where warfighter needs for resources, resource availability, environmental effects, and mission conditions can change from moment to moment. The first challenge occurs when warfighters overstate their individual needs of a shared resource, leading to inefficient allocation. Overstatement may bring local optimization; however, it can cause global inefficiencies that result in a detriment to overall mission success. This challenge is addressed by using computational mechanism design, more specifically, the dynamic Vickrey-Clark-Groves allocation mechanism. The second challenge involves resource availability that may change frequently. Such is the case in a wireless mesh network where routes and bandwidth may vary over even small intervals of time. In such a case, an adaptive quality of service (AQoS) approach is used, and the available resource is allocated using the Dynamic QoS-based Resource Allocation Model (D-Q-RAM). Computational mechanism design is used to allocate sensors, and the AQoS approach allocates the available network bandwidth in a way consistent with the sensor allocation, providing an approach for dealing with resource allocation and adaptation in a dynamic environment. Initial experimental results of applying the approach are reported.</p

Results of SEI Independent Research and Development Projects (FY 2010)

The Software Engineering Institute (SEI) annually undertakes several independent research and development (IRAD) projects. These projects serve to (1) support feasibility studies investigating whether further work by the SEI would be of potential benefit and (2) support further exploratory work to determine whether there is sufficient value in eventually funding the feasibility study work as an SEI initiative. Projects are chosen based on their potential to mature and/or transition software engineering practices, develop information that will help in deciding whether further work is worth funding, and set new directions for SEI work. This report describes the IRAD projects that were conducted during fiscal year 2010 (October 2009 through September 2010).</p