問66
頻出度★☆☆
OSS (Open Source Software) の利用に関する記述のうち, 適切なものはどれか。
平成23年度 秋期 ITパスポート試験 問66
テクノロジ系ソフトウェア › オープンソースソフトウェア
This question's explanation and your answers so far.
解説
問 66
Incorrectア
The OSD clause on “Free Redistribution” states that an OSS license must not restrict the sale or the free distribution of the software, and must not demand a license fee or royalty for doing so. In other words, users bear no obligation to pay the developer for the software itself. In practice, most OSS can be obtained free of charge. In addition, a vendor is free to take payment for products that incorporate OSS, or fees for services such as deployment support and maintenance support, and this is indeed the core of business models based on OSS; but that is payment for a service, not an obligation imposed on the use of the software itself. Therefore the statement that a user “is obligated to pay a fee” is incorrect.
Incorrectイ
The content of this statement is the exact opposite of the OSD clause on “Free Redistribution.” That clause states that a license must not restrict any party from selling the software, nor from giving it away free of charge. In other words, a user of OSS may sell the OSS obtained for a price, and may also distribute it for free. A concrete example is that Linux distributions are offered both as paid packaged products and as free downloads. The statement that it can be neither sold nor distributed free of charge is incorrect.
Incorrectウ
The OSD contains a clause called “No Discrimination Against Fields of Endeavor,” which states that a license must not restrict the use of the software in any particular field. The explanation of this clause explicitly gives the examples that it must not forbid use in business or use in genetic research. In other words, a license that does not permit use in the field of genetic research cannot be recognized as an OSS license in the first place. Being freely usable regardless of purpose, industry, or field is a basic property of OSS, so this statement is incorrect.
- エ
正解 The correct answer is エ. OSS (Open Source Software) is software whose source code is made public and whose users are granted the freedom to use, modify, and redistribute it. What may be called OSS is defined by the OSD (The Open Source Definition), a standard of ten criteria published by the OSI (Open Source Initiative). One of those criteria is the clause on “Derived Works,” which states explicitly that an OSS license must allow people to create derivative works by modifying that OSS, and must allow them to redistribute those works under the same license terms as the original software. Therefore, releasing again as OSS a derivative created by improving publicly available OSS is an act that is inherently permitted in the use of OSS, so エ is appropriate. In fact, copyleft licenses such as the GPL go further and require that a derivative work, when distributed, carry the same license, that is, be released as OSS. This is what makes the results of improvements flow back into the community, giving rise to the development mechanism unique to OSS in which many developers continuously raise the quality. One point to be careful about, however, is that OSS is not work whose copyright has been abandoned (the public domain). The copyright remains with the original author, and users must observe the license conditions, such as keeping the copyright notices, including the license text, and disclosing the source code under a copyleft license.
ここがポイント
- Definitions of OSS and OSD — OSS (Open Source Software) is software whose source code is public and which may be freely used, modified, and redistributed. Its requirements are laid down in the OSD defined by the OSI, and include free redistribution (restricting neither sale nor free distribution, and demanding no license fee), availability of the source code, permission to create derived works and redistribute them under the same license, no discrimination against persons or groups, and no discrimination against fields of endeavor.
- Handling of derivative works and copyright — Releasing as OSS a derivative created by improving the software is permitted, and under copyleft licenses such as the GPL, releasing it under the same license is mandatory. On the other hand, note that OSS does not abandon copyright: users are still required to keep the copyright notices and to comply with the license conditions.
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