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46-736: In 1964, the US Air Force (USAF) decided to use the commercial off-the-shelf Cessna 172F as a lead-in aircraft for student pilots rather than starting them out in the T-37 jet aircraft. The USAF ordered 237 T-41As from Cessna . The first USAF class (67-A) of students began training on the T-41 from the civilian airport in Big Spring, Texas , in August 1965. The T-41B was the US Army version, with

92-665: A 210 hp (160 kW) Continental IO-360 engine and constant-speed propeller in place of the 145 hp (108 kW) Continental O-300 and 7654 fixed-pitch propeller used in the 172 and the T-41A. In 1968, the USAF acquired 52 of the more powerful T-41Cs, which used 210 hp (160 kW) Continental IO-360 and a fixed-pitch climb propeller, for use at the Air Force Academy in Colorado Springs . In 1996,

138-412: A deadline. Software analysis begins with a requirements analysis to capture the business needs of the software. Challenges for the identification of needs are that current or potential users may have different and incompatible needs, may not understand their own needs, and change their needs during the process of software development. Ultimately, the result of analysis is a detailed specification for

184-664: A group is creating a make-work system to justify extra funding, rather than providing a low-cost system which meets the basic needs, regardless of the use of COTS products. Applying the lessons of processor obsolescence learned during the Lockheed Martin F-22 Raptor , the Lockheed Martin F-35 Lightning II planned for processor upgrades during development, and switched to the more widely supported C++ programming language. They have also moved from ASICs to FPGAs . This moves more of

230-840: A major threat. Gartner predicts that "enterprise IT supply chains will be targeted and compromised, forcing changes in the structure of the IT marketplace and how IT will be managed moving forward". Also, the SANS Institute published a survey of 700 IT and security professionals in December 2012 that found that only 14% of companies perform security reviews on every commercial application brought in house, and over half of other companies do not perform security assessments. Instead companies either rely on vendor reputation (25%) and legal liability agreements (14%) or they have no policies for dealing with COTS at all and therefore have limited visibility into

276-551: A reduction in initial cost and development time over an increase in software component-integration work, dependency on the vendor , security issues and incompatibilities from future changes. COTS software and services are built and delivered usually from a third party vendor. COTS can be purchased, leased or even licensed to the general public. COTS can be obtained and operated at a lower cost over in-house development, and provide increased reliability and quality over custom-built software as these are developed by specialists within

322-455: A replacement system. Such obsolescence problems have led to government-industry partnerships, where various businesses agree to stabilize some product versions for government use and plan some future features, in those product lines, as a joint effort. Hence, some partnerships have led to complaints of favoritism, to avoiding competitive procurement practices, and to claims of the use of sole-source agreements where not actually needed. There

368-696: A series of fatal accidents at the US Air Force Academy. Four T-41s remained at the Air Force Academy for the USAFA Flying Team, as well as to support certain academic classes. A number of air forces, including Saudi Arabia and Singapore , purchased various civilian models of the Cessna 172 for use in military training, transport, and liaison roles. While similar to the T-41, these aircraft were not T-41s and were powered by

414-423: Is a COTS software provider. Goods and construction materials may qualify as COTS but bulk cargo does not. Services associated with the commercial items may also qualify as COTS, including installation services, training services, and cloud services. COTS purchases are alternatives to custom software or one-off developments – government-funded developments or otherwise. Although COTS products can be used out of

460-511: Is a framework that provides the viewpoints on the system and its environment , to be used in the software development process . It is a graphical representation of the underlying semantics of a view. The purpose of viewpoints and views is to enable human engineers to comprehend very complex systems and to organize the elements of the problem around domains of expertise . In the engineering of physically intensive systems, viewpoints often correspond to capabilities and responsibilities within

506-408: Is a popular way of managing changes made to the software. Whenever a new version is checked in, the software saves a backup of all modified files. If multiple programmers are working on the software simultaneously, it manages the merging of their code changes. The software highlights cases where there is a conflict between two sets of changes and allows programmers to fix the conflict. A view model

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552-420: Is also the danger of pre-purchasing a multi-decade supply of replacement parts (and materials) which would become obsolete within 10 years. All these considerations lead to compare a simple solution (such as "paper & pencil") to avoid overly complex solutions creating a " Rube Goldberg " system of creeping featurism , where a simple solution would have sufficed instead. Such comparisons also consider whether

598-449: Is correctly incorporated with the newer software. Design involves choices about the implementation of the software, such as which programming languages and database software to use, or how the hardware and network communications will be organized. Design may be iterative with users consulted about their needs in a process of trial and error . Design often involves people expert in aspect such as database design , screen architecture, and

644-833: Is essential to success. This is more easily achieved if the team is small, used to working together, and located near each other. Communications also help identify problems at an earlier state of development and avoid duplicated effort. Many development projects avoid the risk of losing essential knowledge held by only one employee by ensuring that multiple workers are familiar with each component. Software development involves professionals from various fields, not just software programmers but also individuals specialized in testing, documentation writing, graphic design , user support, marketing , and fundraising. Although workers for proprietary software are paid, most contributors to open-source software are volunteers. Alternately, they may be paid by companies whose business model does not involve selling

690-399: Is helpful for new developers to understand the project when they begin working on it. In agile development, the documentation is often written at the same time as the code. User documentation is more frequently written by technical writers . Accurate estimation is crucial at the feasibility stage and in delivering the product on time and within budget. The process of generating estimations

736-422: Is inefficient, difficult to understand, or lacking documentation on its functionality. These standards are especially likely to break down in the presence of deadlines. As a result, testing, debugging, and revising the code becomes much more difficult. Code refactoring , for example adding more comments to the code, is a solution to improve the understandability of code. Testing is the process of ensuring that

782-513: Is integrated or networked with other software products to create a new composite application or a system of systems. The composite application can inherit risks from its COTS components. The US Department of Homeland Security has sponsored efforts to manage supply chain cyber security issues related to the use of COTS. However, software industry observers such as Gartner and the SANS Institute indicate that supply chain disruption poses

828-440: Is often delegated by the project manager . Because the effort estimation is directly related to the size of the complete application, it is strongly influenced by addition of features in the requirements—the more requirements, the higher the development cost. Aspects not related to functionality, such as the experience of the software developers and code reusability, are also essential to consider in estimation. As of 2019 , most of

874-432: Is often used to break down the customer's requirements into pieces that can be implemented by software programmers. The underlying logic of the program may be represented in data-flow diagrams , data dictionaries , pseudocode , state transition diagrams , and/or entity relationship diagrams . If the project incorporates a piece of legacy software that has not been modeled, this software may be modeled to help ensure it

920-401: Is robust to heavy levels of input or usage), integration testing (to ensure that the software is adequately integrated with other software), and compatibility testing (measuring the software's performance across different operating systems or browsers). When tests are written before the code, this is called test-driven development . Production is the phase in which software is deployed to

966-471: The programming language ). Documentation comes in two forms that are usually kept separate—that intended for software developers, and that made available to the end user to help them use the software. Most developer documentation is in the form of code comments for each file, class , and method that cover the application programming interface (API)—how the piece of software can be accessed by another—and often implementation details. This documentation

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1012-512: The COTS product. The use of COTS has been mandated across many government and business programs, as such products may offer significant savings in procurement, development, and maintenance. Motivations for using COTS components include hopes for reduction system whole of life costs. In the 1990s, many regarded COTS as extremely effective in reducing the time and cost of software development . COTS software came with many not-so-obvious tradeoffs –

1058-538: The aircraft were further upgraded to the T-41D, which included an upgrade in avionics and to a constant-speed propeller. Beginning in 1993, the USAF replaced many of the T-41 fleet with the Slingsby T-3A Firefly for the flight-screening role, and for aerobatic training, which was outside the design capabilities of the T-41. The T-3A fleet was indefinitely grounded in 1997 and scrapped in 2006 following

1104-489: The available methodologies are best suited to specific kinds of projects, based on various technical, organizational, project, and team considerations. Another focus in many programming methodologies is the idea of trying to catch issues such as security vulnerabilities and bugs as early as possible ( shift-left testing ) to reduce the cost of tracking and fixing them. In 2009, it was estimated that 32 percent of software projects were delivered on time and budget, and with

1150-447: The avionic design from fixed circuits to software that can be applied to future generations of hardware. COTS components are part of upgrades to the sonar of United States Navy submarines. Software development Software development is the process of designing and implementing a software solution to satisfy a user . The process is more encompassing than programming , writing code , in that it includes conceiving

1196-458: The box, in practice the COTS product must be configured to achieve the needs of the business and integrated to existing organizational systems. Extending the functionality of COTS products via custom development is also an option, however this decision should be carefully considered due to the long term support and maintenance implications. Such customized functionality is not supported by the COTS vendor, so brings its own sets of issues when upgrading

1242-423: The code executes correctly and without errors. Debugging is performed by each software developer on their own code to confirm that the code does what it is intended to. In particular, it is crucial that the software executes on all inputs, even if the result is incorrect. Code reviews by other developers are often used to scrutinize new code added to the project, and according to some estimates dramatically reduce

1288-480: The device itself if the steps are not taken to ensure fair and safe standards are complied with. The standard IEC 62304:2006 "Medical device software – Software life cycle processes" outlines specific practices to ensure that SOUP components support the safety requirements for the device being developed. In the case where the software components are COTS, DHS best practices for COTS software risk review can be applied. Simply being COTS software does not necessarily imply

1334-408: The end user. During production, the developer may create technical support resources for users or a process for fixing bugs and errors that were not caught earlier. There might also be a return to earlier development phases if user needs changed or were misunderstood. Software development is performed by software developers , usually working on a team. Efficient communications between team members

1380-430: The engineering organization. Fitness functions are automated and objective tests to ensure that the new developments don't deviate from the established constraints, checks and compliance controls. Intellectual property can be an issue when developers integrate open-source code or libraries into a proprietary product, because most open-source licenses used for software require that modifications be released under

1426-477: The full functionality. An additional 44 percent were delivered, but missing at least one of these features. The remaining 24 percent were cancelled prior to release. Software development life cycle refers to the systematic process of developing applications . The sources of ideas for software products are plentiful. These ideas can come from market research including the demographics of potential new customers, existing customers, sales prospects who rejected

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1472-656: The goal, evaluating feasibility, analyzing requirements , design , testing and release . The process is part of software engineering which also includes organizational management , project management , configuration management and other aspects. Software development involves many skills and job specializations including programming , testing , documentation , graphic design , user support , marketing , and fundraising . Software development involves many tools including: compiler , integrated development environment (IDE), version control , computer-aided software engineering , and word processor . The details of

1518-500: The industry and are validated by various independent organizations, often over an extended period of time. According to the United States Department of Homeland Security , software security is a serious risk of using COTS software. If the COTS software contains severe security vulnerabilities it can introduce significant risk into an organization's software supply chain . The risks are compounded when COTS software

1564-617: The lack of a fault history or transparent software development process. For well documented COTS software a distinction as clear SOUP is made, meaning that it may be used in medical devices. A striking example of product obsolescence are PlayStation 3 clusters , which used Linux to operate. Sony disabled the use of Linux on the PS3 in April 2010, leaving no means to procure functioning Linux replacement units . In general, COTS product obsolescence can require customized support or development of

1610-562: The needs of the purchasing organization, rather than the commissioning of custom-made, or bespoke , solutions. A related term, Mil-COTS , refers to COTS products for use by the U.S. military. In the context of the U.S. government , the Federal Acquisition Regulation (FAR) has defined "COTS" as a formal term for commercial items, including services, available in the commercial marketplace that can be bought and used under government contract. For example, Microsoft

1656-407: The number of bugs persisting after testing is complete. Once the code has been submitted, quality assurance —a separate department of non-programmers for most large companies—test the accuracy of the entire software product. Acceptance tests derived from the original software requirements are a popular tool for this. Quality testing also often includes stress and load checking (whether the software

1702-403: The performance of servers and other hardware. Designers often attempt to find patterns in the software's functionality to spin off distinct modules that can be reused with object-oriented programming . An example of this is the model–view–controller , an interface between a graphical user interface and the backend . The central feature of software development is creating and understanding

1748-463: The process used for a development effort varies. The process may be confined to a formal, documented standard , or it can be customized and emergent for the development effort. The process may be sequential, in which each major phase (i.e. design, implement and test) is completed before the next begins, but an iterative approach – where small aspects are separately designed, implemented and tested – can reduce risk and cost and increase quality. Each of

1794-424: The product that developers can work from. Software analysts often decompose the project into smaller objects, components that can be reused for increased cost-effectiveness, efficiency, and reliability. Decomposing the project may enable a multi-threaded implementation that runs significantly faster on multiprocessor computers. During the analysis and design phases of software development, structured analysis

1840-466: The product, other internal software development staff, or a creative third party. Ideas for software products are usually first evaluated by marketing personnel for economic feasibility, fit with existing channels of distribution, possible effects on existing product lines, required features , and fit with the company's marketing objectives. In the marketing evaluation phase, the cost and time assumptions become evaluated. The feasibility analysis estimates

1886-503: The project's return on investment , its development cost and timeframe. Based on this analysis, the company can make a business decision to invest in further development. After deciding to develop the software, the company is focused on delivering the product at or below the estimated cost and time, and with a high standard of quality (i.e., lack of bugs) and the desired functionality. Nevertheless, most software projects run late and sometimes compromises are made in features or quality to meet

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1932-445: The risks introduced into their software supply chain by COTS. In the medical device industry, COTS software can sometimes be identified as SOUP ( software of unknown pedigree or software of unknown provenance), i.e., software that has not been developed with a known software development process or methodology, which precludes its use in medical devices. In this industry, faults in software components could become system failures in

1978-427: The software that implements the desired functionality. There are various strategies for writing the code. Cohesive software has various components that are independent from each other. Coupling is the interrelation of different software components, which is viewed as undesirable because it increases the difficulty of maintenance . Often, software programmers do not follow industry best practices, resulting in code that

2024-403: The software, but something else—such as services and modifications to open source software. Computer-aided software engineering (CASE) is tools for the partial automation of software development. CASE enables designers to sketch out the logic of a program, whether one to be written, or an already existing one to help integrate it with new code or reverse engineer it (for example, to change

2070-786: The standard 172 powerplants available in the model year purchased. These included the 145 hp (108 kW) Continental O-300 in pre-1968 aircraft and the 150 and 160 hp (120 kW) Lycoming O-320 in later 172s. With the exception of the T-41A, most variants of the T-41 were certified under the Cessna 175 Skylark type certification. Data from Global Security General characteristics Performance Related development Aircraft of comparable role, configuration, and era Commercial off-the-shelf Commercial-off-the-shelf or commercially available off-the-shelf ( COTS ) products are packaged or canned (ready-made) hardware or software, which are adapted aftermarket to

2116-520: The tools for estimating the amount of time and resources for software development were designed for conventional applications and are not applicable to web applications or mobile applications . An integrated development environment (IDE) supports software development with enhanced features compared to a simple text editor . IDEs often include automated compiling , syntax highlighting of errors, debugging assistance, integration with version control , and semi-automation of tests. Version control

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