The process of developing new information systems has evolved from custom software development to assembly of off-the-shelf components. The change has significantly reduced both the costs and time to develop new capabilities, and as a notable result, e-business systems have been implemented at a very rapid pace. An assembly sequence (components to be assembled, corresponding dates and costs) has several risks including: 1) technical risk: successful (or not) function of assembled components by planned schedule milestones; 2) operational risk: achieving (or not) the desired business value by using the new system of assembled components; and 3) programmatic (schedule and cost) risks: accomplishing the assembly within time and budget constraints. As assembly proceeds, estimates of technical performance and operational value at the time of system completion can be adjusted, and one should consider what early milestones of component assembly suggest about later milestones. The technical community can be both hesitant to reveal and ascertain the results of combining off-the-shelf products into a working system, and it is typical to have significant cost and schedule overruns due to technical problems that are discovered late in system assembly. The operational community can be surprised by the results achieved in applying new capabilities, causing significant changes to what was originally desired from a new system. This paper presents a framework for planning and adjusting milestone sequences in assembling off-the-shelf software components. The framework balances technical and operational risks within established cost and time constraints.

Model-based testing is a new and evolving technique for generating a suite of test cases from requirements.Testers using this approach concentrate on a data model and generation infrastructure instead of hand-crafting individual tests.Several relatively small studies have demonstrated how combinatorial test generation techniques allow testers to achieve broad coverage of the input domain with a small number of tests.We have conducted several relatively large projects in which we applied these techniques to systems with millions of lines of code.Given the complexity of testing, the modelbased testing approach was used in conjunction with test automation harnesses.Since no large empirical study has been conducted to measure efficacy of this new approach, we report on our experience with developing tools and methods in support of model-based testing.The four case studies presented here offer details and results of applying combinatorial test-generation techniques on a large scale to diverse applications.Based on the four projects, we offer our insights into what works in practice and our thoughts about obstacles to transferring this technology into testing organizations.

The author explores anomalous situations which can arise during the processing of database operations on schemas which include referential integrity constraints. A more declarative (as opposed to operational) approach to referential integrity is proposed. He reviews some of the contributions which ANSI Technical Committee X3H2 on Database has made in this area, and which have been reflected in the referential integrity specifications of the forthcoming SQL2 and SQL3 standards. A proposal that replaced the recent compile-time paradigm with a run-time paradigm is included. A correctness proof for this paradigm is provided.>