Jean Mayrand

Assessing the benefits of incorporating function clone detection in a development process

The aim of the experiment presented in this paper is to present an insight into the evaluation of the potential benefits of introducing a function clone detection technology in an industrial software development process. To take advantage of function clone detection, two modifications to the software development process are presented. Our experiment consists of evaluating the impact that these proposed changes would have had on a specific software system if they had been applied over a 3 year period (involving 10000 person-months), where 6 subsequent versions of the software under study were released. The software under study is a large telecommunication system. In total 89 million lines of code have been analyzed. A first result showed that, against our expectations, a significant number of clones are being removed from the system over time. However, this effort is insufficient to prevent the growth of the overall number of clones in the system. In this context the first process change would have added value. We have also found that the second process change would have provided programmers with a significant number of opportunities for correcting problems before customers experienced them. This result shows a potential for improving the software system quality and customer satisfaction

EMERALD: software metrics and models on the desktop

As software becomes more and more sophisticated, industry has begun to place a premium on software reliability. The telecommunications industry is no exception. Consequently software reliability is a strategic business weapon in an increasingly competitive marketplace. In response to these concerns, BNR, Nortel, and Bell Canada developed the Enhanced Measurement for Early Risk Assessment of Latent Defects (Emerald), a decision support system designed to improve telecommunications software reliability. Emerald efficiently integrates software measurements, quality models, and delivery of results to the desktop of software developers. We have found that Emerald not only improves software reliability, but also facilitates the accurate correction of field problems. Our experiences developing Emerald have also taught us some valuable lessons about the implementation and adoption of this type of software tool.

System acquisition based on software product assessment

The procurement of complex software product involves many risks. To properly assess and manage those risks, Bell Canada has developed methods and tools that combine process capability assessment with a static analysis based software product assessment. This paper describes the software product assessment process that is part of our risk management approach. The process and the tools used to conduct a product assessment are described. The assessment is in part based on static source code metrics and inspections. A summary of the lessons learned since the initial implementation in 1993 is provided. Over 20 products totalling more than 100 million lines of code have gone through this process.

Integrating metrics and models for software risk assessment

Enhanced Measurement for Early Risk Assessment of Latent Defects (EMERALD) is a decision support system for assessing reliability risk. It is used by software developers and managers to improve telecommunications software service quality as perceived by the customer and the end user. Risk models are based on static characteristics of source code. This paper shows how a system such as EMERALD can enhance software development, testing, and maintenance by integration of: a software quality improvement strategy; measurements and models; and delivery of results to the desktop of developers in a timely manner. This paper also summarizes empirical experiments with EMERALDs models using data from large industrial telecommunications software systems. EMERALD has been applied to a very large system with over 12 million lines of source code within procedures. Experience and lessons learned are also discussed.

Detection of fault-prone program modules in a very large telecommunications system

Telecommunications software is known for its high reliability. Society has become so accustomed to reliable telecommunications, that failures can cause major disruptions. This is an experience report on application of discriminant analysis based on 20 static software product metrics, to identify fault prone modules in a large telecommunications system, so that reliability may be improved. We analyzed a sample of 2000 modules representing about 1.3 million lines of code, drawn from a much larger system. Sample modules were randomly divided into a fit data set and a test data set. We simulated utilization of the fitted model with the test data set. We found that identifying new modules and changed modules mere significant components of the discriminant model, and improved its performance. The results demonstrate that data on module reuse is a valuable input to quality models and that discriminant analysis can be a useful tool in early identification of fault prone software modules in large telecommunications systems. Model results could be used to identify those modules that would probably benefit from extra attention, and thus, reduce the risk of unexpected problems with those modules.

Process Self-Assessment in an Educational Context

This paper describes a studio in software engineering based on the delivery of a product within the framework of a defined process. The studio is a 3-credit fourth year elective course in computer engineering. Students have to compromise between the effort expended on the product and that expended on the process. The process based on the SEI CMM has been used in professional research labs and was supported by commercial CASE tools. The use of the process is formally assessed by a professional evaluator. A working product was obtained by the team that invested the least effort and were the more liberal regarding the process. They were prototype-oriented. The team that was truly process-oriented expended much more effort than expected and did not deliver an integrated product. The team with a mixed approach followed the proper process and delivered an integrated product, but expended a tremendous amount of effort. The students were unanimous in acclaiming the learning benefits of having the process formally assessed.

Inheritance graph assessment using metrics

Presents a new method integrated in Bell Canadas software acquisition process to assess software. This paper is focused on the assessment of the understandability of the inheritance graph of object-oriented software. The method is based on metrics and on the graphical illustration of the inheritance graph. A technique to decompose the inheritance graph of an object-oriented program into sub-graphs using metrics is described. Metrics are also used to identify complex sub-graphs. On the selected graphs, a technique to improve the understandability of the graphical illustration representing the inheritance graph is also described. This technique is based on extracting the main tree on the inheritance graph. A C++ case study containing 1080 classes is presented, on which this assessment method was applied.