A Verified Information-Flow Architecture

SAFE is a clean-slate design for a highly secure computer system, with pervasive mechanisms for tracking and limiting information flows. At the lowest level, the SAFE hardware supports fine-grained programmable tags, with efficient and flexible propagation and combination of tags as instructions are executed. The operating system virtualizes these generic facilities to present an information-flow abstract machine that allows user programs to label sensitive data with rich confidentiality policies. We present a formal, machine-checked model of the key hardware and software mechanisms used to dynamically control information flow in SAFE and an end-to-end proof of noninterference for this model. We use a refinement proof methodology to propagate the noninterference property of the abstract machine down to the concrete machine level. We use an intermediate layer in the refinement chain that factors out the details of the information-flow control policy and devise a code generator for compiling such information-flow policies into low-level monitor code. Finally, we verify the correctness of this generator using a dedicated Hoare logic that abstracts from low-level machine instructions into a reusable set of verified structured code generators

An Architecture for Information Commerce Systems

The increasing use of the Internet in business and commerce has created a number of new business opportunities and the need for supporting models and platforms. One of these opportunities is information commerce (i-commerce), a special case of ecommerce focused on the purchase and sale of information as a commodity. In this paper we present an architecture for i-commerce systems using OPELIX (Open Personalized Electronic Information Commerce System) [11] as an example. OPELIX provides an open information commerce platform that enables enterprises to produce, sell, deliver, and manage information products and related services over the Internet. We focus on the notion of information marketplace, a virtual location that enables i-commerce, describe the business and domain model for an information marketplace, and discuss the role of intermediaries in this environment. The domain model is used as the basis for the software architecture of the OPELIX system. We discuss the characteristics of the OPELIX architecture and compare our approach to related work in the field

An information architecture for validating courseware

Courseware validation should locate Learning Objects inconsistent with the courseware instructional design being used. In order for validation to take place it is necessary to identify the implicit and explicit information needed for validation. In this paper, we identify this information and formally define an information architecture to model courseware validation information explicitly. This promotes tool-support for courseware validation and its interoperability with the courseware specifications

An information architecture for courseware validation

A lack of pedagogy in courseware can lead to learner rejec- tion. It is therefore vital that pedagogy is a central concern of courseware construction. Courseware validation allows the course creator to specify pedagogical rules and principles which courseware must conform to. In this paper we investigate the information needed for courseware valida- tion and propose an information architecture to be used as a basis for validation

Architecture: a guide to finding information

A guide to finding books and journals in the library

Information Technology of Software Architecture Structural Synthesis of Information System

Information technology of information system software architecture structural synthesis is proposed. It is used for evolutionary models of the software lifecycle, which provides configuration and formation of software to control the realization and recovery of computing processes in parallel and distributed computing resources structures. The technology is applied in the framework of the software requirements analysis, design of architecture, design and integration of software. Method of combining vertices for multilevel graph model of software architecture and automata-based method of checking performance limitations to software are based on the advanced graph model of software architecture. These methods are proposed in the framework of information technology and allow forming a rational structure of the program, as well as checking for compliance with the functional and non-functional requirements of the end user.The essence of proposed information technology is in displaying of the customer's requirements in the current version of the graph model of program complex structure and providing a reconfiguration of the system modules. This process is based on the analysis and processing of the graph model, software module specifications, formation of software structure in accordance with the graph model, software verification and its compilation

Deep Space Network information system architecture study

The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control