Pejman Salehi

A model driven approach for AMF configuration generation

High availability of services is an important requirement for mission critical systems. The Service Availability Forum defines standards like the Availability Management Framework (AMF) to support the realization of high available systems. AMF is a middleware service that coordinates redundant application components to ensure the high availability of the provided services. In order to provide and protect services, AMF requires a configuration that captures the organization of logical entities and their relations. It describes the service providers, the provided services, their types, and the deployment infrastructure. The process of generating an AMF configuration requires the description of the software characteristics as well as the configuration requirements that specify the services to be provided. Due to the large number of parameters to be taken into account, the generation of an AMF configuration can be a difficult and error prone task. This paper proposes a new approach for the automatic generation of AMF configurations. The proposed solution is model driven and is based on UML profiles which capture the concepts related to configuration requirements, software description, and AMF configurations. AMF configurations are generated using ATL based transformations defined between these different profiles.

A UML-Based Domain Specific Modeling Language for the Availability Management Framework

The Service Availability Forum (SA Forum) is a consortium of several telecommunications and computing companies that defines standard solutions for high availability platforms. One of the most important SA Forum services is the Availability Management Framework (AMF) which is responsible for managing the availability of an application running under its control. To achieve this, AMF requires a complete configuration, which consists of several entities organized according to AMF rules and constraints. In this paper, we argue that AMF concepts form a domain for which a domain-specific modeling language can greatly facilitate the generation, analysis and the management of AMF configurations. We define such a language by extending UML through its profiling mechanism and we implement it. More important, we discuss the challenges and the lessons learned in the course of this project.

Checking Service Instance Protection for AMF Configurations

An AMF configuration is a logical organization of resources, components and Service Units (SUs) grouped into Service Groups (SGs), for providing and protecting services defined as Service Instances (SIs). The assignment of SIs to SUs is a runtime operation performed by the Availability Management Framework (AMF) implementation. However, ensuring the capability of the provisioning and the protection of the SIs by the configured resources is a configuration issue. In other words, a configuration is valid if and only if it is capable of providing and protecting the services as required and according to the specified redundancy model. Ensuring this may require the exploration of all possible SI-SU assignments and in some cases different combinations of SIs, a complex procedure in most redundancy models defined in the AMF standard specification. In this paper, we explore the problem of SI protection at configuration time; we investigate and discuss its complexity and identify some special and more tractable cases.

Bridging the Gap between User Requirements and Configuration Requirements

The Service Availability Forum supports the realization of Highly Available systems by means of standards like the Availability Management Framework (AMF), a middleware service that manages the high availability of services provided by applications through the coordination of their redundant components. AMF configurations for applications, capable of providing and protecting services, can be generated from the software and from a set of configuration requirements (CR). The specification of CR requires a good knowledge of the AMF specification. Users/Customers may not have this AMF knowledge and are usually acquainted to specifying high level characteristics of services of interest. This paper introduces an approach aiming at bridging the gap between user requirements and configuration requirements for the design of AMF configurations.

A UML-based domain specific modeling language for service availability management

For critical systems, providing services with minimal interruption is essential. Availability Management Framework (AMF), defined by SA Forum for managing highly-available applications, requires configurations of applications consisting of various entities organized according to AMF-specific rules and constraints. Creating such configurations is difficult due to the numerous constrained entities involved. This paper presents UACL (UML-based AMF Configuration Language) and a supporting implementation that models the AMF domain, providing designers with tools needed to design, edit, and analyze AMF configurations. UACL is an extension of UML through its profiling mechanism and has been designed to represent AMF concepts, their relations, and constraints. We present a UML-based domain specific modeling language (DSML) that models the SA Forum Availability Management Framework (AMF) domain model.Our DSML provides designers with the tools needed for designing, editing, and potentially analyzing AMF configurations.Our DSML has been carefully designed to represent AMF concepts, their relations, and constraints.Our DSML has been implemented using IBM Rational Software Architect.We show the effectiveness of our DSML in designing AMF configurations through a case study.We report on our experience in designing this language and the challenges encountered during this process.