F.Y.B.Sc. Computer Science Semester - I (C:75:25) Solution Set - December 2018 (03/12/2018) Subject Code: 82103 QP Code:59232 Time : 2 ½ Hours Total Marks: 75 Q1 Attempt All(Each of 5 marks) (15) a) Multiple Choice Questions 1) GPL stands for _______ i) Generle Public License ii) General Public License iii) Generic Public License iv) General Private License 2) Which of the following is not a phase of Life Cycle Paradigm / waterfall model? i) Analysis ii) Manufacturing iii) Design iv) Coding 3) _________ is the founder of FSF i) Richard Stallman ii) Denis Ritchie iii) Ken Thomson iv) All of these 4) __________ is a form of licensing in which an author surrenders some but not all rights under copyright law i) Copydown ii) License iii) Copyleft iv) Patent 5) The term BSD stands for ______________ i) Binary software distribution ii) Berkley software distribution iii) Binary software development iv) Berkley software development b) Fill in the blanks (Waterfall model, full, internationalization, Prototyping model, Firefox, localization, chrome, free hardware design, partial, open source software) 1) Waterfall model is a static, sequential and procedural approach in software engineering methodology. 2) full copyleft is when all parts of work can be modified by consecutive authors. 3) localization is the process of adapting software for a specific region or language by adding locale-specific components and translating text. 4) Firefox is a web browser project descended from Mozilla application suite. 5) free hardware design refers to design which can be freely copied, distributed, modified and manufactured. c) Short Answers: 1) What is free software? Ans: Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, not price: users —individually or in cooperation with computer programmers— are free to do what they want with their copies of free software (including profiting from them) regardless of how much is paid to obtain the program. 2) Define Shared software. Ans: It is shared rather than owned. The way to develop and use software more effectively is to share it with others. Sharing is symmetric. 3) Define GCC. Ans: The GNU Compiler Collection (GCC) is a compiler system produced by the GNU Project supporting various programming languages. GCC is a key component of the GNU toolchain. The Free Software Foundation (FSF) distributes GCC under the GNU General Public License (GNU GPL). 4) Draw symbol of copyright. Ans: 5) What isPublic domain software? Ans: Public domain software is software that has been donated to the public domain by its copyright holder. Thus it is no longer copyrighted. Consequently, such software is completely free and can be used by anybody for any purpose without restriction. Q2. Attempt the following (Any THREE): (15) a) List and explain 4 freedoms of free software. Ans: The freedom to run the program, for any purpose. The freedom to study how the program works, and modify it The freedom to redistribute copies. The freedom to distribute copies of modified versions to others. b) Define BSD. Explain its history. BSD licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. This is in contrast to copyleft licenses, which have share-alike requirements. The original BSD license was used for its namesake, the Berkeley Software Distribution (BSD), a Unix-like operating system. The original version has since been revised, and its descendants are referred to as modified BSD licenses. BSD is both a license and a class of license (generally referred to as BSD-like). The modified BSD license (in wide use today) is very similar to the license originally used for the BSD version of Unix. The BSD license is a simple license that merely requires that all code be licensed under the BSD license if redistributed in source code format. BSD (unlike some other licenses) does not require that source code be distributed at all. c) Write a note on following: i) LGPL license ii) Internationalization Ans: LGPL An important corner-case of the GPL requires that only GPL code can link with with GPL libraries, even if the library is contained in a separate file, and the code which uses it contains no GPL code unto itself. This is seen by some as too strict, since such an action could be considered a "use" of the library, not as a modification. In order to allow for such a distinction, the LGPL was created. The LGPL fixes precisely this problem: If someone uses an LGPL work as a library which is symbolically linked with a project, the rest of the project does not have to be put under the LGPL. On the other hand, if any modifications are made to the LGPL'ed work which is distributed along with the software package as a whole, the changes must be made public, similar to the rules of the GPL. The "L" in the LGPL stands for different things for different people. Initially it was considered as a "Library" license, since the clause specifically dealt with issues of linking. However, the GNU Foundation describes this as the "Lesser" GPL, since it gives fewer protections to the work than the GPL does. While the GNU Foundation does not frown upon the use of the LGPL, it encourages the use of the GPL when possible. LGPL makes a clear difference between the code that has been covered by this license (usually software library) and the external code that is just linked to the LGPL covered code. The external code can stay proprietary. However modifications inside the LGPL covered library must be shared with public. Companies usually find LGPL terms acceptable and it is common to find public libraries with this license inside the commercial software. d) Explain the concept ‘Free does not mean no cost.’ Ans: While FOSS is free to the end user, there is a cost associated with developing the software. These costs may be smaller than developing proprietary software, because developing the project under FOSS license means that: Numerous web portals like SourceForge would offer web hosting, content repository, mailing lists and other essential features for free. The cost of advertising a FOSS project (like presenting it in the related conferences) is usually lower. Developing something under GPL may give free access to high quality components (like QT) that are otherwise expensive to buy or not available at all. Still, development of any software first requires the developer time. Only very popular projects may expect to get a high quality code contributions for free. This is a common misunderstanding about FOSS, in no small part because nearly all FOSS programs are available free of charge. For example when the text editor Emacs was first released Richard Stallman charged from time to time to get copies. Developers have the choice to charge under most FOSS licenses, although they rarely choose to. The only requirement to be a truly FOSS project is that the publisher provides the source code with the program, and to allow the user to edit that code. On top of the initial cost of purchasing software, there are other ongoing costs associated with all software. This can come in the form of support agreements, the cost of customization, training costs support personnel and other sources. This is true of both traditional commercial software and FOSS programs. There is a large and active debate about which type of software is more expensive over the long run for large corporations, for individual users there is little to no question that FOSS is cheaper by far. e) Discuss about Copyleft. Ans: Copyleft Copyleft is a general method for making a program (or other work) free (in the sense of freedom, not “zero price”), and requiring all modified and extended versions of the program to be free as well. Copyleft (a play on the word copyright) is the practice of offering people the right to freely distribute copies and modified versions of a work with the stipulation that the same rights be preserved in derivative works down the line. Copyleft software licenses are considered protective or reciprocal, as contrasted with permissive free software licenses. Copyleft is a form of licensing, and can be used to maintain copyright conditions for works ranging from computer software, to documents, to art, to scientific discoveries and instruments in medicine. In general, copyright law is used by an author to prohibit recipients from reproducing, adapting, or distributing copies of their work. In contrast, under copyleft, an author may give every person who receives a copy of the work permission to reproduce, adapt, or distribute it, with the accompanying requirement that any resulting copies or adaptations are also bound by the same licensing agreement. Copyleft licenses for software require that information necessary for reproducing and modifying the work must be made available to recipients of the binaries. The source code files will usually contain a copy of the license terms and acknowledge the authors. Copyleft type licenses are a novel use of existing copyright law to ensure a work remains freely available. f) Differentiate between Open source software and Closed software. Ans: Open source Closed source Licensor distributed source code. Licensor distributes object code only, source code is kept a trade secret. Modification are permitted. Modification are prohibited. Licensee may do its own All upgrades, support and development and support or hire development are done by licensor. any third party to do it. Fees, if any, are for integration, Fees are for the software's license, packing, support, and consulting.